Substituted benzazoloporphyrazines for polymerization and surface attachment and articles formed therefrom

ABSTRACT

The present invention provides an article of manufacture formed from a substrate and a benzazoloporphyrazine bound to the substrate. The article may take a variety of different forms and may be for example an electrochromic display, a molecular capacitor, a battery, a solar cell, or a molecular memory device. Methods of making such articles, along with compounds, methods and intermediates useful for making such benzazoloporphyrazines, are also described.

RELATED APPLICATIONS

This application claims the benefit of United States Provisional PatentApplication Ser. No. 60/687,288, filed Jun. 3, 2005, the disclosure ofwhich is incorporated by reference herein in its entirety.

STATEMENT OF GOVERNMENT SUPPORT

This invention was made with government support under a grant from theCenter for Nanoscience Innovation for Defense and DARPA/DMEA awardnumber H94003-04-2-0404. The US Government has certain rights to thisinvention.

FIELD OF THE INVENTION

The present invention concerns articles of manufacture formed fromsubstrates having benzazoloporphyrazine compounds coupled thereto,useful as among other things molecular memory devices, as well ascompounds, methods and intermediates useful for making such articles.

BACKGROUND OF THE INVENTION

Phthalocyanine dyes are widely explored for use in such diverseapplications as textile colorants (Christie, R. M. Colour Chemistry,Royal Society of Chemistry: Cambridge, UK, 2001), nonlinear opticalgeneration and limiting (de la Torre, G. et al., J. Mater. Chem. 1998,8, 1671-1683; Calvete, M. et al., Synth. Met. 2004, 141, 231-243),photodynamic therapy (Allen, C. M. et al., J. Porphyrins Phthalocyanines2001, 5, 161-169), photovoltaics (Nazeeruddin, M. et al., J. PorphyrinsPhthalocyanines 1999, 3, 230-237; Petritsch, K. et al., Synth. Met.1999, 102, 1776-1777), sensors (Zhou, R. et al., Appl. Organomet. Chem.1996, 10, 557-577), electrochromic displays (Jiang, J. et al., InSupramolecular Photosensitive and Electroactive Materials, Nalwa, H. S.Ed., Academic Press: San Diego, Calif., 2001, 188-189), and informationstorage (Li, J. et al., J. Org. Chem. 2000, 65, 7379-7390; Gryko, etal., J. Mater. Chem. 2001, 11, 1162-1180; Gross, T. et al., Inorg. Chem.2001, 40, 4762-4774; Schweikart, K.-H. et al., J. Mater. Chem. 2002, 12,808-828; Schweikart, K.-H. et al., Inorg. Chem. 2003, 42, 7431-7446;Wei, L. et al., J. Org. Chem. 2004, 69, 1461-1469)

In molecular electronics, ordered phthalocyanine materials are generallysought over disordered materials, and the routes to ordered materialscan vary widely from sublimation of phthalocyanines into crystallinelayers, Langmuir-Blodgett film formation, mesomorphism, and backbonepolymerization (Achar, B. N. et al., J. Polym. Sci. Polym. Chem. Ed.1982, 20, 1785-1790; Venkatachalam, S. et al., J. Polym. Sci. Part B1994, 32, 37-52; Gürek, A. G. et al., J. Porphyrins Phthalocyanines1997, 1, 67-76; Gürek, A. G.; Bekaroglu, O. J. PorphyrinsPhthalocyanines 1997, 1, 227-237; Wörhle, D. et al., J. PorphyrinsPhthalocyanines 2000, 4, 491-497; Kingsborough, R. P.; Swager, T. M.Angew. Chem. Int. Ed. 2000, 39, 2897-2900).

Backbone polymerization of phthalocyanines is distinguished from theaxially connected or “shish-kebab” phthalocyanines (Hanack, M. et al.,In Handbook of Conducting Polymers, Skotheim, T. A., Elsenbaumer, R. L.,and Reynolds, J. R., Eds., Marcel Dekker, New York, 1998, 381). Backbonepolymerization of phthalocyanines is difficult, owing partly to thelimited solubility of most phthalocyanines and partly to limitations ofthe geometry of phthalocyanines. The advantages of backbone polymers ofphthalocyanines relative to non-covalently assembled phthalocyanines are(1) improved thermal and chemical stability of the short and long rangestructure, (2) reproducible preparation of materials without the use ofexpensive or delicate instrumentation, and sometimes (3) the addition ofthrough-bond mechanisms of electronic communication between thecomponent monomers as a complement to through-space mechanisms of energytransfer and/or conductivity.

Most efforts at preparing phthalocyanine polymers have utilized thephthalocyanine macrocyclization reaction as the material-forming step,with bridged or bilateral building blocks such as1,2,4,5-tetracyanobenzene or dicyanobenzenes linked by alkyl chains orother intermediary groups. This strategy typically results intwo-dimensional sheets of fused or linked pigments. Another approach isto prepare oligomers of fused phthalocyanines with polymerizable endgroups, which also gives two-dimensional products. The ladder oligomersprepared by Hanack and coworkers are the best example of a linear onedimensional phthalocyanine material (Hauschel, B. et al., J. Chem. Soc.,Chem. Commun. 1995, 2449-2451; Hanack, M.; Stihler, P. Eur. J. Org.Chem. 2000, 303-311). However, the stepwise synthesis used for sucholigomers is not well suited to the preparation of polymers bearing manyphthalocyanine macrocycles. Kingsborough and Swager prepared athiophene-linked metallophthalocyanine polymer via electropolymerizationof thiophene end groups. The resulting material is described as “nearlylinear”, but this polymer allows for rotation of the phthalocyanines andis not likely to be shape-persistent. The electroactive linking groupsplay a large role in the character of the resulting polymer. The fusedlinkages in the ladder oligomers and the phthalocyanine sheets also havea significant effect on the photochemical and electrochemical propertiesof the individual chromophores of the resulting material. In many casesthis perturbation may be beneficial and intentional. However, theseperturbation effects are not easily predicted and therefore complicatethe design of electronic materials. Accordingly, there is a need for newcompounds and methods for preparing linear (non-fused) materials.

SUMMARY OF THE INVENTION

A first aspect of the present invention is an article of manufacturecomprising a substrate and a benzazoloporphyrazine bound to thesubstrate. The benzazoloporphyrazine is preferably bound to thesubstrate by a bond (e.g. a covalent bond) to the 2 position of an azologroup thereof. The article may take a variety of different forms and maybe for example an electrochromic display, a molecular capacitor, abattery, a solar cell, or a molecular memory device.

In some embodiments the benzazoloporphyrazine is a member of a sandwichcoordination compound such as a double-decker sandwich or triple-deckersandwich coordination compound.

In some embodiments the benzazoloporphyrazine is a member of a polymerof at least two linked benzazoloporphyrazines (e.g., 2, 3 or 5 to 20, 50or 100 or more), with each of the benzazoloporphyrazines preferablylinked to an adjacent benzazoloporphyrazine by a bond (directly or by anintervening linker) to the 2 position of an azolo group thereof. In somesuch embodiments, some or all of the benzazoloporphyrazines in thepolymer may in turn be sandwich coordination compounds to provide apolymer of sandwich coordination compounds bound to the substrate.

A second aspect of the invention is a benzazoloporphyrazine compoundhaving at least one independently selected substituent R at a 2 positionof an azolo group thereof, wherein R is preferably a surface attachmentgroup or cross-coupling group. In some embodiments the compound is atrans-bis(2-R-benzazolo)porphyrazine having a pair of substituents R ateach 2 position of each of the pair of oppositely facing azolo groupsthereof; in some embodiments the compound is a 2-R-benzazoloporphyrazinecompound having a single substituent R at the 2 position of the azologroup thereof; in some embodiments the compound is atetrakis(2-R-benzazolo)porphyrazine compound having an independentlyselected substituent R at each 2 position of each of the four azologroups thereof.

A further aspect of the invention is a method of making an article ofmanufacture, comprising the steps of: (a) providing a substrate; andthen (b) coupling a first benzazoloporphyrazine as described above tothe substrate. The method may further comprise the step of (c) couplingat least one additional benzazoloporphyrazine as described above to thefirst benzazoloporphyrazine, such as in a gradient polymerization.

A further aspect of the present invention is a sandwich coordinationcompound, wherein at least one member thereof is a benzazoloporphyrazineas described herein.

A further aspect of the present invention is a method of making anarticle of manufacture, comprising the steps of: (a) providing asubstrate; and then (b) coupling a first sandwich coordination compoundas described herein to the substrate. The method may optionally comprisethe step of (c) coupling at least one additional sandwich coordinationcompound containing a benzazoloporphyrazine to the benzazoloporphyrazineof the first sandwich coordination compound, as in a gradientpolymerization.

A further aspect of the present invention is a polymer comprising from 2to 50 or 100 or more benzazoloporphyrazines covalently coupled to oneanother.

A further aspect of the present invention is a polymer of from 2 to 50or 100 or more linked sandwich coordination compounds, wherein each ofthe sandwich coordination compounds comprises a benzazoloporphyrazine asdescribed herein linked to a benzazoloporphyrazine of an adjacentsandwich coordination compound.

A further aspect of the present invention is a method of making anarticle of manufacture, comprising the steps of: (a) providing asubstrate; and then (b) coupling a polymer as described above to thesubstrate.

The foregoing and other objects and aspects of the present invention areexplained in greater detail in the drawings herein and the specificationset forth below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1. Structures of two disubstituted phthalocyanines. The N-N axisbisects two inner nitrogen atoms and two opposing benzo rings. The axisequally can be displayed bisecting the NH—NH atoms. (A) A2,17-disubstituted phthalocyanine, with substituents of a non-parallelalignment. (B) A 2,16-disubstituted phthalocyanine, with parallel butnot collinear substituents.

FIG. 2. Absorption and emission spectra for tetrasubstitutedbenzimidazo-porphyrazines.

FIG. 3. (A) Absorption spectra for Fb-11. (B) Absorption spectra forFb-13. (C) Emission spectra for Fb-11 (excitation at 435, 600, and 630nm). (D) Emission spectra for Fb-13 (excitation at 435, 630, and 640nm).

FIG. 4. Absorption and emission spectra for low symmetryzinc-benzimidazo-porphyrazines.

FIG. 5. Structures of three known types of heteroleptic triple deckerlanthanide sandwich complexes.

FIG. 6. A type-c triple decker bearing a tether for surface attachment.

FIG. 7. Camshaft rotation of a type-c triple decker for surfaceattachment.

FIG. 8. Representation of the type-a triple decker bearing the compactall-carbon tether. The tripod is attached to the (central)phthalocyanine ligand and aligned along one of the N-N axes of thephthalocyanine.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A. Definitions

“Halo” as used herein refers to any suitable halogen, including —F, —Br,and —I.

“Cyano” as used herein refers to a —CN group.

“Hydroxyl” as used herein refers to an —OH group.

“Nitro” as used herein refers to an —NO₂ group.

“Alkyl” as used herein alone or as part of another group, refers to astraight or branched chain hydrocarbon containing from 1 to 10, 20 or 40or more carbon atoms. Representative examples of alkyl include, but arenot limited to, methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl,iso-butyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl,3-methylhexyl, 2,2-dimethylpentyl, 2,3-dimethylpentyl, n-heptyl,n-octyl, n-nonyl, n-decyl, and the like. “Loweralkyl” as used herein, isa subset of alkyl, in some embodiments preferred, and refers to astraight or branched chain hydrocarbon group containing from 1 to 4carbon atoms. Representative examples of lower alkyl include, but arenot limited to, methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl,tert-butyl, and the like. The term “alkyl” or “loweralkyl” is intendedto include both substituted and unsubstituted alkyl or loweralkyl unlessotherwise indicated and these groups may be substituted with groupsselected from halo, alkyl, haloalkyl, alkenyl, alkynyl, cycloalkyl,cycloalkylalkyl, aryl, arylalkyl, heterocyclo, heterocycloalkyl,hydroxyl, alkoxy, alkenyloxy, alkynyloxy, haloalkoxy, cycloalkoxy,cycloalkylalkyloxy, aryloxy, arylalkyloxy, heterocyclooxy,heterocyclolalkyloxy, mercapto, alkyl-S(O)_(m), haloalkyl-S(O)_(m),alkenyl-S(O)_(m), alkynyl-S(O)_(m), cycloalkyl-S(O)_(m),cycloalkylalkyl-S(O)_(m), aryl-S(O)_(m), arylalkyl-S(O)_(m),heterocyclo-S(O)_(m), heterocycloalkyl-S(O)_(m), amino, alkylamino,alkenylamino, alkynylamino, halo alkylamino, cycloalkylamino,cycloalkylalkylamino, arylamino, arylalkylamino, heterocycloamino,heterocycloalkylamino, disubstituted-amino, acylamino, acyloxy, ester,amide, sulfonamide, urea, alkoxyacylamino, aminoacyloxy, nitro or cyanowhere m=0, 1 or 2.

“Alkenyl” as used herein alone or as part of another group, refers to astraight or branched chain hydrocarbon containing from 1 to 10, 20, or40 or more carbon atoms (or in loweralkenyl 1 to 4 carbon atoms) whichinclude 1 to 4 double bonds in the normal chain. Representative examplesof alkenyl include, but are not limited to, vinyl, 2-propenyl,3-butenyl, 2-butenyl, 4-pentenyl, 3-pentenyl, 2-hexenyl, 3-hexenyl,2,4-heptadiene, and the like. The term “alkenyl” or “loweralkenyl” isintended to include both substituted and unsubstituted alkenyl orloweralkenyl unless otherwise indicated and these groups may besubstituted with groups as described in connection with alkyl andloweralkyl above.

“Alkynyl” as used herein alone or as part of another group, refers to astraight or branched chain hydrocarbon containing from 1 to 10, 20 or 40or more carbon atoms (or in loweralkynyl 1 to 4 carbon atoms) whichinclude 1 triple bond in the normal chain. Representative examples ofalkynyl include, but are not limited to, 2-propynyl, 3-butyryl,2-butynyl, 4-pentynyl, 3-pentynyl, and the like. The term “alkynyl” or“loweralkynyl” is intended to include both substituted and unsubstitutedalkynyl or loweralknynyl unless otherwise indicated and these groups maybe substituted with the same groups as set forth in connection withalkyl and loweralkyl above.

“Alkoxy,” as used herein alone or as part of another group, refers to analkyl or loweralkyl group, as defined herein, appended to the parentmolecular moiety through an oxy group, —O—. Representative examples ofalkoxy include, but are not limited to, methoxy, ethoxy, propoxy,2-propoxy, butoxy, tert-butoxy, pentyloxy, hexyloxy and the like.

“Acyl” as used herein alone or as part of another group refers to a—C(O)R radical, where R is any suitable substituent such as aryl, alkyl,alkenyl, alkynyl, cycloalkyl or other suitable substituent as describedherein.

“Haloalkyl,” as used herein alone or as part of another group, refers toat least one halogen, as defined herein, appended to the parentmolecular moiety through an alkyl group, as defined herein.Representative examples of haloalkyl include, but are not limited to,chloromethyl, 2-fluoroethyl, trifluoromethyl, pentafluoroethyl,2-chloro-3-fluoropentyl, and the like.

“Alkylthio,” as used herein alone or as part of another group, refers toan alkyl group, as defined herein, appended to the parent molecularmoiety through a thio moiety, as defined herein. Representative examplesof alkylthio include, but are not limited, methylthio, ethylthio,tert-butylthio, hexylthio, and the like.

“Aryl,” as used herein alone or as part of another group, refers to amonocyclic carbocyclic ring system or a bicyclic carbocyclic fused ringsystem having one or more aromatic rings. Representative examples ofaryl include, azulenyl, indanyl, indenyl, naphthyl, phenyl,tetrahydronaphthyl, and the like. The term “aryl” is intended to includeboth substituted and unsubstituted aryl unless otherwise indicated andthese groups may be substituted with the same groups as set forth inconnection with alkyl and loweralkyl above.

“Amino” as used herein means the radical —NH₂.

“Alkylamino” as used herein alone or as part of another group means theradical —NHR, where R is an alkyl group.

“Cycloalkyl,” as used herein alone or as part of another group, refersto a saturated or partially unsaturated cyclic hydrocarbon groupcontaining from 3, 4 or 5 to 6, 7 or 8 carbons

(which carbons may be replaced in a heterocyclic group as discussedbelow). Representative examples of cycloalkyl include, cyclopropyl,cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. Theserings may be optionally substituted with additional substituents asdescribed herein such as halo or loweralkyl.

“Thiocyanato” refers to an —SCN group.

“Sulfoxyl” is —S(═O)R¹R², where R¹ and R² are alkyl or aryl.

“Sulfonyl” is —R¹—S(═O)₂R², where R¹ and R² are alkyl or aryl.

“Amido” is —RC(═O)NR¹R², where R alkyl or aryl, and R¹ and R² are H,alkyl or aryl.

“Carbamoyl” —ROC(═O)NR¹R², where R alkyl or aryl, and R¹ and R² are H,alkyl or aryl.

“Linkers” (linking group, linker group, etc.) that may be used to formcovalent conjugates of two functional moieties are known in the art. Theparticular linking group employed in carrying out the present inventionis not critical, and linking groups that may be used include, but arenot limited to, those disclosed in U.S. Pat. No. 6,624,317 to Lee etal., U.S. Pat. No. 5,650,399 to Rokita et al., and U.S. Pat. No.5,122,368 to Greenfield et al. In general, the linking group maycomprise an aliphatic, aromatic, or mixed aliphatic and aromatic group(e.g., alkyl, aryl, alkylaryl, etc.) and contain one or more heteroatoms such as N, O, S, etc.

“Porphyrazine” is used generically herein to refer to compounds having ageneral core structure as follows:

in unsubstituted form, as well as such compounds with substitutionsthereon, (e.g., compounds as shown below with various substituentsthereon). Porphyrazines may be substituted with any suitable group,including ring systems and fused ring systems such as benzazolo groupsas discussed further below. Substituents on non-linking positions of theporphyrazines (or on benzo or naphtho or other annulated rings) include,but are not limited to, alkyl, alkenyl, alkynyl, cycloalkyl, aryl(including phenyl), halo, hydroxy, alkoxy, alkylthio, pyridyl, cyano,thiocyanato, nitro, amino, alkylamino, acyl, sulfoxyl, sulfonyl, amido,and carbamoyl (all of which may be substituted or unsubstituted). Morepreferred substituents are aryl (including phenyl), cycloalkyl, alkyl,halogen, alkoxy; alkylthio, perfluoroalkyl, perfluoroaryl, pyridyl,cyano, thiocyanato, nitro, amino, alkylamino, acyl, sulfoxyl, sulfonyl,amido, and carbamoyl. Most preferred substituents include methyl,t-butyl, butoxy, fluoro, and H (no substituent).

“Sub-porphyrazine” as used herein, refers to a structure like aporphyrazine as given above, except with one less pyrrole ring therein.The tribenzo analogue of a sub-porphyrazine is “sub-phthalocyanine”.

“Benzazoloporphyrazine” as used herein includes substituted orunsubstituted porphyrazines as described above, particularly with one,two three or four benzazolo groups fused thereto at the b, g, l and/or qbond positions, which benzazolo groups may be substituted orunsubstituted as noted above. Examples include:2-R-5,6-benzazoloporphyrazines such as:

trans-bis(2-R-5,6-benzazolo)porphyrazines such as:

and tetrakis(2-R-5,6-benzazolo)porphyrazines such as:

where X in all of the foregoing is for example NR¹ (forbenzimidazoporphyrazines), 0 (for benzoxazoporphyrazines), S (forbenzthiazoporphyrazines), and Se (for benzselenazoporphyrazines), R¹ isfor example H or alkyl, and the 2 position of the azolo groups arenumbered, M is a metal or a pair of hydrogen atoms, and the rings may beunsubstituted as shown or further substituted as described above andbelow (e.g., hydrogens on the benzazolo groups may be replaced with likesubstituents as noted above in connection with porphyrazines). Note thatcertain compounds may exist as different regioisomers, depending uponthe position of the ring substituent X therein.

Particular examples of all of the foregoing are:

-   2-R-5,6-benzimidazoporphyrazines;-   trans-bis(2-R-5,6-benzimidazo)porphyrazines;-   tribenzo(2-R-5,6-benzimidazo)porphyrazines;-   trans-dibenzo-bis(2-R-5,6-benzimidazo)porphyrazines;-   tetrakis(2-R-5,6-benzimidazo)porphyrazines;-   2-R-5,6-benzoxazoporphyrazines;-   trans-bis(2-R-5,6-benzoxazo)porphyrazines;-   tribenzo(2-R-5,6-benzoxazo)porphyrazines;-   trans-dibenzo-bis(2-R-5,6-benzoxazo)porphyrazines;-   tetrakis(2-R-5,6-benzoxazo)porphyrazines;-   2-R-5,6-benzthiazoporphyrazines;-   trans-bis(2-R-5,6-benzthiazo)porphyrazines;-   tribenzo(2-R-5,6-benzthiazo)porphyrazines;-   trans-dibenzo-bis(2-R-5,6-benzthiazo)porphyrazines;-   tetrakis(2-R-5,6-benzthiazo)porphyrazines;-   2-R-5,6-benzselenazoporphyrazines;-   trans-bis(2-R-5,6-benzselenazo)porphyrazines;-   tribenzo(2-R-5,6-benzselenazo)porphyrazines;-   trans-dibenzo-bis(2-R-5,6-benzselenazo)porphyrazines; and-   tetrakis(2-R-5,6-benzselenazo)porphyrazines.

All of which may be substituted or unsubstituted as described furtherabove and below. The terms “sandwich coordination compound” or “sandwichcoordination complex” refer to a compound of the formula L^(n)M^(m-1),where each L is a heterocyclic ligand (as described below), each M is ametal, n is 2 or more, most preferably 2 (as for a double-deckersandwich coordination compound) or 3 (as for a triple decker sandwichcoordination compound), and each metal is positioned between a pair ofligands and bonded to one or more heteroatom (and typically a pluralityof heteroatoms, e.g., 2, 3, 4, 5) in each ligand (depending upon theoxidation state of the metal). Thus sandwich coordination compounds arenot organometallic compounds such as ferrocene, in which the metal isbonded to carbon atoms. The ligands in the sandwich coordinationcompound are generally arranged in a stacked orientation (i.e., aregenerally cofacially oriented and axially aligned with one another,although they may or may not be rotated about that axis with respect toone another). See, e.g., D. Ng and J. Jiang, Sandwich-type heterolepticphthalocyaninato and porphyrinato metal complexes, Chemical SocietyReviews 26, 433-442 (1997). The metals M are generally comprised of thelanthanide series (Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb,Lu) as well as Y, In, La, Bi, and the actinides. In fact the onlylanthanide that has not been incorporated into a sandwich complex is theradioactive element Pm. Double-decker and triple-decker, sandwichcoordination compounds are preferred.

The term “homoleptic sandwich coordination compound” refers to asandwich coordination compound as described above wherein all of theligands L are the same.

The term “heteroleptic sandwich coordination compound” refers to asandwich coordination compound as described above wherein at least oneligand L is different from the other ligands therein.

A linker is a molecule used to couple two different molecules, twosubunits of a molecule, or a molecule to a substrate. When all arecovalently linked, they form units of a single molecule.

A substrate is a, preferably solid, material suitable for the attachmentof one or more molecules. Substrates can be formed of materialsincluding, but not limited to glass, plastic, silicon, minerals (e.g.quartz), semiconducting materials, ceramics, metals, etc.

“Surface attachment group” as used herein refers to a functional grouphaving a protected or unprotected reactive site or group thereon, suchas a carboxylic acid, alcohol, thiol, selenol or tellurol group, or aphosphono (e.g. dihydroxyphosphoryl), alkenyl (e.g., ethenyl) andalkynyl (e.g., ethynyl) group. “Surface attachment groups” as usedherein may be monodentate or monopodal, but also encompassesmultidentate or multipodal (e.g., bipod, tripod, quadrupod, etc.)surface attachment groups unless specified to the contrary. Whileencompassing a variety of substituents as discussed below, a surfaceattachment group is not H, and is not an unsubstituted and saturatedalkyl (e.g., —(CH₂)_(n)CH₃ where n is 1 to 7). The surface attachmentgroup may be unprotected or protected with a suitable protecting groupin accordance with known techniques. Examples of surface attachmentgroups include but are not limited to carboxy, phosphono, iodo, bromo,chloro, cyano, amino, alkenyl, alkynyl, hydroxy, mercapto, selenyl,telluro, S-acetylthio, Se-acetylseleno, Te-acetyltelluro. The surfaceattachment group may be substituted directly on the compound or linkedby means of an intervening linker group (e.g., the groups can beattached at the terminus of an alkyl or aryl tether). The tethers cancomprise single or polypodal tethers. Preferred polypodal tethersinclude 4-(4-allylhepta-1,6-dien-4-yl)phenyl,4-[4-(3-phosphonopropyl)-1,7-diphosphonohept-4-yl]phenyl,4-(3-vinylpenta-1,4-dien-3-yl)biphen-4′-yl,4-[2-(carboxymethyl)-1,3-dicarboxyprop-2-yl]phenyl, and3-ethynylpenta-1,4-diyn-3-yl.

“Cross-coupling group” as used herein refers to a group on one moleculewhich can be utilized in conjunction with a corresponding group onanother molecule to covalently couple the two molecules underappropriate reaction conditions. The groups used in a given couplingreaction may be different with respect to each other or may beidentical, as in a homocoupling reaction. The group(s) and reactionconditions will depend upon the particular technique employed. Examplesinclude but are not limited to groups utilized in Glaser (or Eglinton)coupling, Cadiot-Chodkiewicz coupling, Sonogashira coupling, Heck orWitting reactions, Suzuki coupling, etc. of two different triple deckers(generating a phenylene or biphenyl linker joining a block copolymer).While encompassing a variety of substituents as discussed below, across-coupling group is not H, and is not an unsubstituted and saturatedalkyl (e.g., —(CH₂)_(n)CH₃ where n is 1 to 7). The cross-coupling groupmay be unprotected or protected with a suitable protecting group inaccordance with known techniques. The cross-coupling group may besubstituted directly on the molecule or linked by means of a linkergroup. Examples of cross-coupling groups include halo, alkenyl, alkynyl,amine, etc.

The disclosures of all United States patent references cited herein areto be incorporated herein in their entirety.

B. Compounds and Methods of Synthesis

The present invention provides a method of making atrans-bis(2-R-benzazoloporphyrazine) having at pair of substituents R ateach 2 position of a pair of oppositely facing azolo groups thereof,wherein R is a surface attachment group or cross-coupling group Examplesof such compounds include but are not limited to compounds of FormulaIIa or IIb:

wherein:

M is a metal or a pair of hydrogens;

X is selected from the group consisting of NR¹, O and S, and Se;

R is a surface attachment group or cross-coupling group; and

R¹ is absent or when X is N is H, C1-C40 linear or branched, substitutedor unsubstituted alkyl; and

R² is any suitable substituent as described above for non-linkingpositions of the porphyrazines including, but are not limited to, alkyl,alkenyl, alkynyl, cycloalkyl, aryl (including phenyl), halo, hydroxy,alkoxy, alkylthio, pyridyl, cyano, thiocyanato, nitro, amino,alkylamino, acyl, sulfoxyl, sulfonyl, amido, and carbamoyl (all of whichmay be substituted or unsubstituted). More preferred substituents arearyl (including phenyl), cycloalkyl, alkyl, halogen, alkoxy, alkylthio,perfluoroalkyl, perfluoroaryl, pyridyl, cyano, thiocyanato, nitro,amino, alkylamino, acyl, sulfoxyl, sulfonyl, amido, and carbamoyl. Mostpreferred substituents include methyl, t-butyl, butoxy, fluoro, and H(no substituent).

Or, an adjacent pair of R² groups on the same ring may form a fused orannulated ring or ring system (including unsubstituted ring systems andring systems substituted one or more times, (e.g., 1, 2, 4, 6, 8 times)with a suitable substituent, such as independently selected R²substituents as described above (for example as described in U.S. Pat.No. 6,420,648 to Lindsey at columns 24-27).

Or, an adjacent pair of R² groups on separate proximal benzo rings (forexample, the eight pairs of adjacent R² groups identified by asterisksin IIa and IIb above) may be linked by a linker group (as discussedfurther below).

A method of making compounds of Formulas IIa-b (one embodiment of whichis exmplified by Scheme 7 below) involves reacting a compound of FormulaIII:

with a trihaloisoindolenine to produce saidtrans-bis(2-R-benzazoloporphyrazine)compound. The reaction can becarried out in accordance with known techniques, such as described inU.S. Pat. No. 4,061,654 to Idelson. In some embodiments R² may representanother compound of formula III linked by a linker group as describedabove, which linkage may be carried out in accordance with knowntechniques (See, e.g., Kobayashi, N.; Kobayashi, Y.; Osa T. J. Am. Chem.Soc. 1993, 115, 10994-10995; Kobayashi, N. Chem. Commun. 1998, 487-488;Drew, D. M.; Leznoff, Chem. Commun. 1994, 623). The reaction conditionsare not critical and in general the reaction may be carried out at roomtemperature in any suitable solvent. Typically the reaction is carriedout in the presence of an acid acceptor and a hydroquinone compoundwhich can donate hydrogen atoms. The trihaloisoindolenine may be asdescribed in U.S. Pat. No. 4,061,654, such as a compound of Formula IV:

wherein. X², X³, and X⁴ are each halo, preferably chloro and each R² isas given above.

The present invention also provides 2-R-benzazoloporphyrazine compoundshaving at least one (e.g., one, two, three, four) independently selectedsubstituent R at a 2 position of an azolo group thereof, wherein R is asurface attachment group or cross-coupling group. Such compounds includebut are not limited to compounds of Formula V:

wherein each of M, X, R, R¹ and R² are as given above. Methods of makingsuch compounds (one embodiment of which is exmplified by Scheme 6 below)generally involve reacting a compound of Formula III:

wherein each of X, R, R¹ and R² are as given above with a substituted orunsubstituted boron-subporphyrazine such as a boron-subphthalocyanine(e.g., as illustrated by Formula XX) (or a correspondingaluminum-subphthalocyanine) in an organic solvent (e.g., a polar proticor aprotic solvent, a high boiling point aromatic solvent) at anelevated temperature to produce the desired 2-R benzazoloporphyrazinecompound. In some embodiments R² may represent another compound offormula III linked by a linker group as described above.

where each R² is as given above, and where B has a suitable counterionsuch as a halide, triflate, tosylate, alkoxy or aryloxy group.

The present invention also provides a method of making a2-R-benzazoloporphyrazine compound (including but not limited to thoseof Formula V above) by reacting a compound of Formula VI:

wherein each of X, R, R¹ and R² is as given above with a compound ofFormula VII:

wherein each R² is as given above. The reaction is generally carried outin an alcohol (e.g., butanol, pentanol, hexanol, or mixtures thereof) inthe presence of an alkyl amine or metal base such as DBU, and optionallyin the presence of a metal halide such as MgCl₂ or ZnCl₂, to produce thedesired compound. In some embodiments R² may represent another compoundof formula VII linked by a linker group as described in connection withformula III above.

The present invention further providestetrakis(2-R-benzazolo)porphyrazine compounds having four substituents Rat each 2 position of each azolo group thereof, wherein R is a surfaceattachment group or cross-coupling group. Examples of such compoundsinclude but are not limited to compounds of Formula VIIIa-d:

wherein each of M, X, R, R¹ and R² are as given above. Methods of makingsuch compounds may be carried out by tetramerizing a compound of FormulaIII:

in a polar protic solvent at an elevated temperature to produce thetetrakis compound. In some embodiments R² may represent another compoundof formula III linked by a linker group as described above.

Another method of making a tetrakis(2-R benzazolo)porphyrazine(including but not limited to compounds of Formulas VIIIa-d above) iscarried out by reacting a compound of Formula VI:

(wherein each of X, R, R¹ and R² is as given above). The reaction isgenerally carried out in an alcohol (e.g., butanol, pentanol, hexanol,or mixtures thereof) in the presence of an alkyl amine such as DBU ormetal base such as sodium hydroxide, and optionally in the presence of ametal halide such as MgCl₂ or ZnCl₂, to produce the desired compound. Insome embodiments R² may represent another compound of formula VI linkedby a linker group as described above.

Compound of Formula III:

wherein each of X, R, R¹ and R² is as given above can be made byreacting a compound of Formula VI:

(wherein each of X, R, R¹ and R² is as given above) in either (a) apolar protic solvent such as methanol (optionally with a cosolvent suchas THF) with an alkoxide base (such as NaOMe) and ammonia gas at anelevated temperature, or (b) in a polar aprotic solvent such as DMF withNaNH₂, to produce the compound of Formula III.

The compound of Formula VI as given above can in turn be made byreacting a compound of Formula IX:

(where X′ is NH₂, SH, OH, or SeH), with an aldehyde of the formula RCHO(where R is as given above) in a polar aprotic solvent (typically a highboiling point alcohol or polar aprotic solvent such as ethanol oracetonitrile) in the presence of an oxidant (preferably O₂) to produce areaction product; and then optionally (but preferably when X is N as inthe case with Formula IX above) reacting the reaction product with acompound of the formula R¹X⁵, where R¹ is as given above and X⁵ is halo,tosyl, or triflate, to produce said compound of Formula VI.

When it is desired to produce compounds of Formula VI where X is otherthan N, the general route to compounds of Formula IX can be utilized asshown below, and the compounds of Formula IX (where X is other than N)can be cyclized by reaction with RCHO in like manner as described above.

A general route to:

Compounds of Formula IX where X is N can be made in accordance withknown techniques or by reacting a compound of Formula X:

in a polar aprotic solvent with a cyanation reagent to produce saidcompound of Formula IX One example of such a reaction is shown in Scheme1 below. The reaction is typically carried out in a polar aproticsolvent, DMF and/or DMSO, preferably at an elevated temperature (e.g.,greater than 100° C. but preferably less than 140° C.). Any suitablecyanation reagent can be used, such as: 1) Stoichiometric (or excess)CuCN in polar aprotic solvent (a) Rosenmund, K. W.; Struck, E. Chem.Ber. 1919, 52, 1749; b) von Braun, J.; Manz, G. Liebigs Ann. Chem. 1931,488, 111); 2) Catalytic copper in nonpolar solvent, with catalytic KIand excess NaCN (a) Zanon, J.; Klapars, A.; Buchwald, S. L. J. Am. Chem.Soc. 2003, 125, 2891-2892); 3) Catalytic Palladium reagents (a)[Pd(acetate)₂ or Pd(CN)₂; with excess KCN; in DMF] Takagi K.; Okamoto,T.; Sakakibara, Y.; Oka, S. Chem. Lett. 1973, 471-474; b) [Pd(PPh₃)₄;with excess KCN; in THF] Sekiya, A.; Ishiwara, N. Chem. Lett. 1975,277-278; c) [Pd(PPh₃)₄; with excess Zn(CN)₂; in THF] Tschaen, D. M.;Desmond, R.; King, A. O.; Fortin, M. C.; Pipik, B.; King, S.; Verhoeven,T. R. Synth. Commun. 1994, 24, 887-890; d) [Pd(PPh₃)₄; with excesstrimethylsilylcyanide(TMSCN); in triethylamine] Chatani, N.; Hanafusa,T. J. Org. Chem., 1986, 51, 4711-1716; e) [Pd(acetate)₂, with added(1,5-bis(diphenylphosphino)pentane); with excess KCN; in toluene]Sundermeier, M.; Zapf, A.; Beller, M.; Sans, J. Tetrahedron Lett. 2001,42, 6707-6710); 4) Catalytic Nickel reagents such as a) [Ni(PPh₃)₄ orNi(P(cyclohexyl)₃)₄; with excess NaCN; in EtOH] Cassar, L. J.Organometal. Chem. 1973, 54, C57-C58; b) [Ni(PPh₃)₄; with excess KCN; inhexamethylphosphoramide (HMPA)] Sakakibara, Y.; Ido, Y.; Sasaki, K.;Sakai, M.; Uchino, N. Bull. Chem. Soc. Jpn. 1993, 66, 2776-2778; etc.

Metals and metalation. Benzazoloporphyrazines of the invention may bemetalated with any suitable metal in accordance with known metalationtechniques concurrently with or subsequent to their formation. See,e.g., U.S. Pat. No. 6,208,553. Suitable metals include but are notlimited to 2Li(I), Pd(II), Pt(II), Mg(II), Zn(II), Al(III), Ga(III),In(III), Sn(IV), Cu(II), Ni(II), and Si(IV). Where the metal istrivalent or tetravalent a counterion or (if necessary a substituent R²as in the case of an alkoxy group on Ga(III)) is included as necessary,also in accordance with known techniques.

C. Surface Attachment Groups

As noted above, benzazolopoprhyrazines of the invention can besubstituted at the 2 position of an azolo group thereof with a surfaceattachment group, which may be in protected or unprotected form. Asurface attachment group may be a reactive group coupled directly to theazolo group, or coupled to the azolo group by means of an interveninglinker. Linkers L can be aryl, alkyl, heteroaryl, heteroalkyl (e.g.,oligoethylene glycol), peptide, polysaccharide, etc. Examples of surfaceattachment groups (with the reactive site or group in unprotected form)include but are not limited to:

-   4-carboxyphenyl,-   carboxymethyl,-   2-carboxyethyl,-   3-carboxypropyl,-   2-(4-carboxyphenyl)ethynyl,-   4-(2-(4-carboxyphenyl)ethynyl)phenyl,-   4-carboxymethylphenyl,-   4-(3-carboxypropyl)phenyl,-   4-(2-(4-carboxymethylphenyl)ethynyl)phenyl;-   4-hydroxyphenyl,-   hydroxymethyl,-   2-hydroxyethyl,-   3-hydroxypropyl,-   2-(4-hydroxyphenyl)ethynyl,-   4-(2-(4-hydroxyphenyl)ethynyl)phenyl,-   4-hydroxymethylphenyl,-   4-(2-hydroxyethyl)phenyl,-   4-(3-hydroxypropyl)phenyl,-   4-(2-(4-hydroxymethylphenyl)ethynyl)phenyl;-   4-mercaptophenyl,-   mercaptomethyl,-   2-mercaptoethyl,-   3-mercaptopropyl,-   2-(4-mercaptophenyl)ethynyl,-   4-(2-(4-mercaptophenyl)ethynyl)phenyl,-   4-mercaptomethylphenyl,-   4-(2-mercaptoethyl)phenyl,-   4-(3-mercaptopropyl)phenyl,-   4-(2-(4-mercaptomethylphenyl)ethynyl)phenyl;-   4-selenylphenyl,-   selenylmethyl,-   2-selenylethyl,-   3-selenylpropyl,-   2-(4-selenylphenyl)ethynyl,-   4-selenylmethylphenyl,-   4-(2-selenylethyl)phenyl,-   4-(3-selenylpropyl)phenyl,-   4-selenylmethylphenyl,-   4-(2-(4-selenylphenyl)ethynyl)phenyl;-   4-tellurylphenyl,-   tellurylmethyl,-   2-tellurylethyl,-   3-tellurylpropyl,-   2-(4-tellurylphenyl)ethynyl,-   4-(2-(4-tellurylphenyl)ethynyl)phenyl,-   4-tellurylmethylphenyl,-   4-(2-tellurylethyl)phenyl,-   4-(3-tellurylpropyl)phenyl,-   4-(2-(4-tellurylmethylphenyl)ethynyl)phenyl;-   4-(dihydroxyphosphoryl)phenyl,-   (dihydroxyphosphoryl)methyl,-   2-(dihydroxyphosphoryl)ethyl,-   3-(dihydroxyphosphoryl)propyl,-   2-[4-(dihydroxyphosphoryl)phenyl]ethynyl,-   4-[2-[4-(dihydroxyphosphoryl)phenyl]ethynyl]phenyl,-   4-[(dihydroxyphosphoryl)methyl]phenyl,-   4-[2-(dihydroxyphosphoryl)ethyl]phenyl,-   4-[2-[4-(dihydroxyphosphoryl)methylphenyl]ethynyl]phenyl;-   4-(hydroxy(mercapto)phosphoryl)phenyl,-   (hydroxy(mercapto)phosphoryl)methyl,-   2-(hydroxy(mercapto)phosphoryl)ethyl,-   3-(hydroxy(mercapto)phosphoryl)propyl,-   2-[4-(hydroxy(mercapto)phosphoryl)phenyl]ethynyl,-   4-[2-[4-(hydroxy(mercapto)phosphoryl)phenyl]ethynyl]phenyl,-   4-[hydroxy(mercapto)phosphoryl)methyl]phenyl,-   4-[2-(hydroxy(mercapto)phosphoryl)ethyl]phenyl,-   4-[2-[4-(hydroxy(mercapto)phosphorypmethylphenyl]ethynyl]phenyl;-   4-cyanophenyl,-   cyanomethyl,-   2-cyanoethyl,-   3-cyanopropyl,-   2-(4-cyanophenyl)ethynyl,-   4-[2-(4-cyanophenyl)ethynyl]phenyl,-   4-(cyanomethyl)phenyl,-   4-(2-cyanoethyl)phenyl,-   4-[2-[4-(cyanomethyl)phenyl]ethynyl]phenyl;-   4-cyanobiphenyl;-   4-aminophenyl,-   aminomethyl,-   2-aminoethyl,-   3-aminopropyl,-   2-(4-aminophenyl)ethynyl,-   4-[2-(4-aminophenyl)ethynyl]phenyl,-   4-aminobiphenyl;-   4-formylphenyl,-   4-bromophenyl,-   4-iodophenyl,-   4-vinylphenyl,-   4-ethynylphenyl,-   4-[2-(trimethylsilyl)ethynyl]phenyl,-   4-[2-(triisopropylsilyl)ethynyl]phenyl,-   4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl;-   formyl,-   bromo,-   iodo,-   bromomethyl,-   chloromethyl,-   ethynyl,-   vinyl,-   allyl;-   4-(ethynyl)biphen-4′-yl,-   4-[2-(triisopropylsilyl)ethynyl]biphen-4′-yl,-   3,5-diethynylphenyl;-   4-(bromomethyl)phenyl, and-   2-bromoethyl.

In addition to the monodentate linker-surface attachment groupsdescribed above, multidentate linkers can be employed [Nikitin, K. Chem.Commun. 2003, 282-283; Hu, J.; Mattern, D. L. J. Org. Chem. 2000, 65,2277-2281; Yao, Y.; Tour, J. M. J. Org. Chem. 1999, 64, 1968-1971; Fox,M. A. et al. Langmuir, 1998, 14, 816-820; Galoppini, E.; Guo, W. J. Am.Chem. Soc. 2001, 123, 4342-4343; Deng, X. et al. J. Org. Chem. 2002, 67,5279-5283; Hector Jr., L. G. et al. Surface Science, 2001, 494, 1-20;Whitesell, J. K.; Chang, H. K. Science, 1993, 261, 73-76; Galoppini, E.et al. J. Am. Chem. Soc. 2002, 67, 7801-7811; Siiman, O. et al.Bioconjugate Chem. 2000, 11, 549-556]. Tripodal linkers bearing thiol,carboxylic acid, alcohol, or phosphonic acid units are particularlyattractive for firmly anchoring a molecular device on a planar surface.Specific examples of such linkers are built around the triphenylmethaneor tetraphenylmethane unit, including the following:

-   1,1,1-tris [4-(S-acetyl thiomethyl)phenyl]methyl,-   4-{1,1,1-tris[4-(S-acetylthiomethyl)phenyl]methyl}phenyl,-   1,1,1-tris [4-(dihydroxyphosphoryl)phenyl]methyl,-   4-{1,1,1-tris [4-(dihydroxyphosphoryl)phenyl]methyl}phenyl,-   1,1,1-tris [4-(dihydroxyphosphorylmethyl)phenyl]methyl,-   4-{1,1,1-tris [4-(dihydroxyphosphorylmethyl)phenyl]methyl}phenyl.    All as described in Balakumar, Muthukumaran and Lindsey, U.S. patent    application Ser. No. 10/867,512 (filed Jun. 14, 2004). See also.    Lindsey, Loewe, Muthukumaran, and Ambroise, US Patent Application    Publication No. 20050096465 (Published May 5, 2005), particularly    paragraph 51 thereof. Additional examples of multidentate linkers    include but are not limited to: Alkene surface attachment groups (2,    3, 4 carbons) such as:-   3-vinylpenta-1,4-dien-3-yl,-   4-(3-vinylpenta-1,4-dien-3-yl)phenyl,-   4-(3-vinylpenta-1,4-dien-3-yl)biphen-4′-yl,-   4-allylhepta-1,6-dien-4-yl,-   4-(4-allylhepta-1,6-dien-4-yl)phenyl,-   5-(1-buten-4-yl)nona-1,8-dien-5-yl,-   4-[5-(1-buten-4-yl)nona-1,8-dien-5-yl]phenyl,-   4-[5-(1-buten-4-yl)nona-1,8-dien-5-yl]biphen-4′-yl, etc.

Alkyne surface attachment groups (2, 3, 4 carbons) such as:

-   3-ethynylpenta-1,4-diyn-3-yl,-   4-(3-ethynylpenta-1,4-diyn-3-yl)phenyl,-   4-(3-ethynylpenta-1,4-diyn-3-yl)biphen-4′-yl,-   4-propargylhepta-1,6-diyn-4-yl,-   4-(4-propargylhepta-1,6-diyn-4-yl)phenyl,-   4-(4-propargylhepta-1,6-diyn-4-yl)biphen-4′-yl,-   5-(1-butyn-4-yl)nona-1,8-diyn-5-yl,-   4-[5-(1-butyn-4-yl)nona-1,8-diyn-5-yl]phenyl,-   4-[5-(1-butyn-4-yl)nona-1,8-diyn-5-yl]biphen-4′-yl,

Alcohol surface attachment groups (1, 2, 3 carbons), such as:

-   2-(hydroxymethyl)-1,3-dihydroxyprop-2-yl,-   4-[2-(hydroxymethyl)-1,3-dihydroxyprop-2-yl]phenyl,-   4-[2-(hydroxymethyl)-1,3-dihydroxyprop-2-yl]biphen-4′-yl,-   3-(2-hydroxyethyl)-1,5-dihydroxypent-3-yl,-   4-[3-(2-hydroxyethyl)-1,5-dihydroxypent-3-yl]phenyl,-   4-[3-(2-hydroxyethyl)-1,5-dihydroxypent-3-yl]biphen-4′-yl,-   4-(3-hydroxypropyl)-1,7-dihydroxyhept-4-yl,-   4-[4-(3-hydroxypropyl)-1,7-dihydroxyhept-4-yl]phenyl,-   4-[4-(3-hydroxypropyl)-1,7-dihydroxyhept-4-yl]biphen-4′-yl, etc.,

Thiol surface attachment groups (1, 2, 3 carbons) such as:

-   2-(mercaptomethyl)-1,3-dimercaptoprop-2-yl,-   4-[2-(mercaptomethyl)-1,3-dimercaptoprop-2-yl]phenyl,-   4-[2-(mercaptomethyl)-1,3-dimercaptoprop-2-yl]biphen-4′-yl,-   3-(2-mercaptoethyl)-1,5-dimercaptopent-3-yl-   4-[3-(2-mercaptoethyl)-1,5-dimercaptopent-3-yl]phenyl,-   4-[3-(2-mercaptoethyl)-1,5-dimercaptopent-3-yl]biphen-4′-yl,-   4-(3-mercaptopropyl)-1,7-dimercaptohept-4-yl,-   4-[4-(3-mercaptopropyl)-1,7-dimercaptohept-4-yl]phenyl,-   4-[4-(3-mercaptopropyl)-1,7-dimercaptohept-4-yl]biphen-4′-yl etc.,

Selenyl surface attachment groups (1, 2, 3 carbons), such as:

-   2-(selenylmethyl)-1,3-diselenylprop-2-yl,-   4-[2-(selenylmethyl)-1,3-diselenylprop-2-yl]phenyl,-   4-[2-(mercaptomethyl)-1,3-dimercaptoprop-2-yl]biphen-4′-yl,-   3-(2-selenylethyl)-1,5-diselenylpent-3-yl,-   4-[3-(2-selenylethyl)-1,5-diselenylpent-3-yl]phenyl,-   4-[3-(2-selenylethyl)-1,5-diselenylpent-3-yl]biphen-4′-yl,-   4-(3-selenylpropyl)-1,7-diselenylhept-4-yl,-   4-[4-(3-selenylpropyl)-1,7-diselenylhept-4-yl]phenyl,-   4-[4-(3-selenylpropyl)-1,7-diselenylhept-4-yl]biphen-4′-yl, etc.

Phosphono surface attachment groups (1, 2, 3 carbons), such as:

-   2-(phosphonomethyl)-1,3-diphosphonoprop-2-yl,-   4-[2-(phosphonomethyl)-1,3-diphosphonoprop-2-yl]phenyl,-   4-[2-(phosphonomethyl)-1,3-diphosphonoprop-2-yl]biphen-4′-yl,-   3-(2-phosphonoethyl)-1,5-diphosphonopent-3-yl,-   4-[3-(2-phosphonoethyl)-1,5-diphosphonopent-3-yl]phenyl,-   4-[3-(2-phosphonoethyl)-1,5-diphosphonopent-3-yl]biphen-4′-yl,-   4-(3-phosphonopropyl)-1,7-diphosphonohept-4-yl,-   4-[4-(3-phosphonopropyl)-1,7-diphosphonohept-4-yl]phenyl,-   4-[4-(3-phosphonopropyl)-1,7-diphosphonohept-4-yl]biphen-4′-yl,    etc., and

Carboxylic acid surface attachment groups (1, 2, 3 carbons), such as:

-   2-(carboxymethyl)-1,3-dicarboxyprop-2-yl,-   4-[2-(carboxymethyl)-1,3-dicarboxyprop-2-yl]phenyl,-   4-[2-(carboxymethyl)-1,3-dicarboxyprop-2-yl]biphen-4′-yl,-   3-(2-carboxyethyl)-1,5-dicarboxypent-3-yl,-   4-[3-(2-carboxyethyl)-1,5-dicarboxypent-3-yl]phenyl,-   4-[3-(2-carboxyethyl)-1,5-dicarboxypent-3-yl]biphen-4′-yl,-   4-(3-carboxypropyl)-1,7-dicarboxyhept-4-yl,-   4-[4-(3-carboxypropyl)-1,7-dicarboxyhept-4-yl]phenyl,-   4-[4-(3-carboxypropyl)-1,7-dicarboxyhept-4-yl]biphen-4′-yl, etc.

D. Cross-coupling Groups and Polymers

Compounds of the present invention, as individual ring systems or assandwich coordination compounds thereof, can be linked as linearpolymers in like manner as described in U.S. Pat. No. 6,777,516 to Li,Gryko and Lindsey. Examples of cross-coupling groups include but are notlimited to groups J² and J³ below, which may be linked directly to thecompound of the invention or by an intervening linker L. Linkers L canbe aryl, alkyl, heteroaryl, heteroalkyl (e.g., oligoethylene glycol),peptide, polysaccharide, etc. The cross-coupling group may be simply areactive attachment group or moiety (e.g., —R′ where R′ is a reactivegroup such as bromo), or may comprise a combination of an interveninglinker group coupled to a reactive group (e.g., —R″R′, where R′ is areactive group and R″ is an intervening group such as a hydrophilicgroup).

Particular examples of linkers between porphyrazines include, but arenot limited to, 4,4′-diphenylethyne, 4,4′-diphenylbutadiyne,4,4′-biphenyl, 1,4-phenylene, 4,4′-stilbene, 1,4-bicyclooctane,4,4′-azobenzene, 4,4′-benzylideneaniline, and 4,4″-terphenyl.

Dyads. The synthesis of dyads of triple deckers can proceed via severaldifferent types of reactions. The reactions of interest include Glaser(or Eglinton) coupling of two identical triple deckers (generating abutadiyne linker), Cadiot-Chodkiewicz coupling of two different tripledeckers (generating a butadiyne linker), Sonogashira coupling of twodifferent triple deckers (generating an ethyne linker), Heck or Wittigreactions of two different triple deckers (generating an alkene linker),Suzuki coupling of two different triple deckers (generating a phenyleneor biphenyl linker), etc. Other reactions can also be employed.

J¹—L-TD-L—J² + J³—L-TD-L—J⁴ J² J³ Reaction Type —B(OH)₂ —Cl, —Br, —ISuzuki

—Cl, —Br, —I Sonogashira

Glaser

Cadiot-Chodkiewicz —CHO —Br, —I Wittig —HC═CH₂ —Br, —I Heck

Polymers. The methods for synthesis of polymeric arrays of tripledeckers include but are not restricted to use of the following types ofreactions:

-   -   Glaser (or Eglinton) coupling of a monomeric triple decker        (generating a butadiyne linker)    -   Cadiot-Chodkiewicz coupling of two different triple deckers        (generating a butadiyne linker joining a block copolymer)    -   Sonogashira coupling of two different triple deckers (generating        an ethyne linker joining a block copolymer)    -   Heck or Witting reactions of two different triple deckers        (generating an alkene linker joining a block copolymer)    -   Suzuki coupling of two different triple deckers (generating a        phenylene or biphenyl linker joining a block copolymer)    -   We also can polymerize triple deckers bearing substituents such        as two or more thiophene groups (generating an oligothiophene        linker) or two or more pyrrole groups (generating a polypyrrole        linker).

The synthesis of the polymers can be performed using stepwise methods orusing polymerization methods. Both methods generally require tworeactive groups attached to the triple decker in order to prepare apolymer where the triple deckers are integral components of the polymerbackbone. (An alternative design yields pendant polymers where thetriple deckers are attached via one linkage to the polymer backbone.)The stepwise synthetic method generally requires the use of protectinggroups to mask one reactive site, and one cycle of reactions theninvolves coupling followed by deprotection. In the polymerization methodno protecting groups are employed and the polymer is prepared in aone-flask process.

The polymerizations can take place in solution or can be performed withthe polymer growing from a surface. The polymerization can be performedbeginning with a solid support as in solid-phase peptide or DNAsynthesis, then removed, purified, and elaborated further for specificapplications. The polymerization can also be performed with the nascentpolymer attached to an electroactive surface, generating the desiredelectronic material in situ.

Gradient polymers. Polymers can be created that are composed ofidentical units, or dissimilar units as in block copolymers or randomcopolymers. Alternatively, the polymerization can be performed to createa linear array where the composition of different triple deckers isorganized in a gradient. This latter approach affords the possibility ofcreating a molecular capacitor where the potential of stored chargeincreases (or decreases) in a systematic manner along the length of thearray. The gradient polymers are created in the following manner. Apolymerizable unit (triple decker or linker) is attached to a surface(solid resin as for solid-phase syntheses, or an electroactive surface).The first triple decker (TD¹) is added and the coupling reagents areadded in order to perform the polymerization (e.g., a Glaser coupling).Then the solid-phase is washed to remove the coupling reagents (copperreagents in the case of the Glaser coupling) and any unreacted TD¹. Thenthe second triple decker (TD²) is added followed by coupling reagentsand the polymerization is allowed to continue. The same wash procedureis performed again and then the third triple decker (TD³) is addedfollowed by coupling reagents and the polymerization is allowed tocontinue. Repetition of this process enables the systematic constructionof a linear array of triple deckers with graded oxidation potentials.The final polymer is then cleaved from the solid phase (if the resin isemployed for synthesis) or used directly (if the synthesis is performedon an electroactive surface). The polymerizable groups can be any of thetype described above using the various name reactions (Glaser,Sonogashira, Cadiot-Chodkiewicz, Heck, Wittig, Suzuki, etc.). The finalpolymeric product is comprised of domains of the various triple deckers[(TD¹)_(n)] joined via linkers in a linear array.

Additional information on specific reaction types is provided below.

Glaser Coupling. This coupling reaction, discovered by Glaser over acentury ago (Glaser, C. Ber. 1869, 2, 422), is still very commonly usedto prepare symmetrical butadiynes by the coupling of terminal ethynes. Avariety of conditions can be employed.

(1) Copper reagent. Originally the organic cuprous derivative wasisolated first and then oxidized. Later, it was found that the cuprousderivative can be formed in situ. The portion of cuprous salt whichcould be employed successfully may vary from 0.2 to 600% of thetheoretical amount. Catalytic quantities (0.2%-0.5%) of cuprous saltsare employed mostly with hydrophilic ethynes. Generally, the ratio ofethyne to Cu⁺ should be kept higher than 1. Ammonium or amine compoundsshould also be present (Cameron, M. D.; Bennett, G. E. J. Org. Chem.1957, 22, 557).

(2) Oxidizing agents. Air and oxygen are most frequently employed asoxidizing agents. Other oxidizing agents such as potassium ferricyanide,hydrogen peroxide, and cupric salts have also been employed (Viehe, H.G. Ed: Chemistry of Acetylene, Marcel Dekker, New York, 1969, p. 597).It has been proved, however, in all cases, that the cupric ion is thetrue oxidizing agent (Eglinton, G.; McCrae, W. Adv. Org. Chem. 1963, 4,225).

(3) Time and temperature. In general, room temperature is sufficient andalso convenient. The reaction time varies between minutes and hours.

(4) Solvents. Pyridine is a good solvent for ethynes and their cuprousderivatives. Tertiary amides are also excellent solvents and increasethe coupling speed with a stoichiometric quantity of cuprous salt.However, many kinds of solvents have been successfully employed for theindividual ethynes.

(5) Ethynes. The method is applicable to almost all symmetricalcouplings, no matter what the functional groups are. Yields are good andappear to be limited mostly by the instability of the butadiyne-linkedmaterials formed in the reaction. However, this coupling method cannotbe applied to ethynes with strongly complexing functional groups (suchas phosphine), or certain metal derivatives, which are unstable underthese reaction conditions (Bohlmann, F. Ber. 1951, 84, 545).

This conventional self-coupling of terminal ethynes has been modified by(1) Pd(0)-CuI catalyzed self-coupling in the presence of chloroacetoneand benzene (Rossi, R.; Carpita, A.; Bigelli, C. Tetrahedron Lett. 1985,523), (2) Pd(II)-Cu(I) catalyzed self-coupling in the presence ofstoichiometric iodine (Liu, Q.; Burton, D. J.; Tetrahedron Lett. 1997,38, 4371), (3) Reaction of lithium dialkyl diarylborates with iodine(Pelter, A.; Smith, K.; Tabata, M. J. Chem. Soc. Chem. Commun. 1975,857).

Eglinton Coupling. This method was based on the fact that in Glasercouplings, the true oxidizing agents are cupric salts. In 1956, Eglintonand Galbraith proposed the method which involves a cupric salt oxidationin pyridine (Eglinton, G.; Galbraith, A. R. Chem. Ind. 1956, 737.). Thiscondition was modified by Breslow in the middle 1980s (O'Krongly, D.;Denmeade, S. R.; Chiang, M. Y.; Breslow, R. J. Am. Chem. Soc. 1985, 107,5544), which employed cupric/cuprous couples in oxygen free pyridine.This method is very commonly used today. Pyridine has been mostlyemployed as a good solubilizing and buffering agent. Other amines canalso be employed, such as morpholine and tetramethylethylenediamine. Inaddition, other solvents can also be added. The reaction speed increaseswith the acidity of the acetylenic proton; alkyl ethynes react slowerthan aryl ethynes and butadiynes as in Glaser coupling. The cuprousderivative does not form in significant quantities but appears to be thereaction intermediate.

Straus Coupling. Under conditions of Glaser coupling in acidic media, anenyne can be formed, as first demonstrated by Straus in 1905 (Straus, F.Liebigs Ann. 1905, 342, 190). The original experimental process consistsof refluxing for a few hours, then an acetic acid solution of a drycuprous derivative is added under an inert gas. The only enyne formed ishead-to-tail coupled, whereas the head-to-head coupled, enyne couldnever be detected.

Cadiot-Chodkiewicz Coupling. For the preparation of unsymmetricalbutadiynes, Glaser coupling of two different terminal ethynes inevitablygives a mixture of butadiynes. The Cadiot-Chodkiewicz coupling method,proposed in 1957 (Chodkiewicz, W. Ann. Chim. 1957, 2, 819), provides adirected route to couple two different ethyne units. TheCadiot-Chodkiewicz coupling method consists of the condensation ofethynes with halogenated ethynes in the presence of cuprous salt and asuitable amine. It is noteworthy that under the reaction conditions,1-halogenoethynes can undergo a self-coupling to the correspondingsymmetrical butadiynes (Chodkiewicz, W. Ann. Chim. 1957, 2, 819):

(1) Cuprous Salt. The cuprous ethyne derivative is assumed to be thereactive intermediate. The cuprous species is regenerated in thecondensation and can be employed in catalytic amounts (about 1-5%). Thislow concentration of cuprous ion reduces almost entirely theself-coupling of the halogenoethynes.

(2) Basic Agent. This reaction does not occur in acid media. A base isnecessary to neutralize the acid resulting from the condensation. Aminesare good solvents which hinder the self-coupling reaction as well asoxidation of the reaction medium. The efficiency of amines decreases asfollows: primary>secondary>tertiary.

(3) Solvent. Good solubility of the teuninal ethyne in the reactionmedium is required. A minimum solubility of the cuprous derivative isalso essential. Alcohols are frequently employed for aryl ethynes.Ethers can be used with scarcely soluble compounds. Tertiary amides arevery good solvents for terminal ethynes and for cuprous derivatives, andare often employed with scarcely soluble compounds.

(4) Nature of the 1-halogenoacetylene. Among chloro-, bromo- andiodo-derivatives the 1-bromoethynes are the most suitable. Generally the1-bromoethynes are sufficiently reactive toward derivatives. At theother extremes, 1-iodoethynes are strongly oxidizing toward the cuprousion and favor the self-coupling reaction, while 1-chloroethynes exhibitlow reactivity.

Suzuki Coupling. Suzuki cross coupling of aryl halides with arylboronicacids has emerged as an extremely powerful tool to form biaryl compounds(For reviews, see: (a) Miyaura, N.; Suzuki, A. Chem. Rev. 1995, 95,2457. (b) Suzuki, A. J. Organomet. Chem. 1999, 576, 147). Thismethodology has been extensively studied with respect to palladiumsources, ligands, additives, solvents etc. (Littke, A. F.; Fu, G. C.Angew. Chem., Int. Ed. 1998, 37, 3387). To date, the compoundscontaining a biaryl linkage could be prepared under very mild conditionsin very good yield with a wide range of substituents under therespective coupling conditions.

Oligomers and/or polymers containing triple decker units with biaryllinkages under Suzuki coupling conditions may be prepared. These kindsof polymers are expected to display interesting optical and/orelectronic properties and thus find applications as functionalmaterials. We have prepared various triple decker building blocksbearing aryl halide groups, while the stable nature of boronic acids(thermally, air and moisture stable) makes it feasible to prepare thecorresponding triple decker building blocks bearing boronic acid groups.The triple decker monomers containing halides and boronic acid groupsare thus treated under Suzuki coupling conditions to afford the desiredmolecular architecture.

Sonogashira coupling. The Sonogashira coupling of an ethyne and an arylhalide affords the corresponding ethyne-linked compound. The Sonogashirareaction can be performed using Pd(PPh₃)₂Cl₂ and CuI in dilute solutionin toluene and triethylamine under mild temperatures (35° C.), or usingPd₂(dba)₃ with tri-o-tolylphosphine in toluene and triethylamine undermild temperatures (35° C.). Other amine-containing solvents can beemployed as well.

Wittig reaction. The Wittig reaction involves the coupling of an alkylhalide and an aldehyde or ketone, generating an alkene. This is one ofthe most powerful methods of carbon-carbon bond formation and involvestreatment of the alkyl halide with a phosphine (e.g.,triphenylphosphine) followed by treatment with a strong base (e.g.,n-butyl lithium) and reaction with the carbonyl compound.

Polymers of the present invention may be represented by Formula XX:

X¹X^(m+1))_(m)

wherein:

m is at least 1 (e.g., 1, 2, or 3 to 10, 20, 50 or 100 or more); and

X¹ through X^(m+1) are sandwich coordination compounds (each of whichmay be the same or different).

Specific examples of polymers of Formula I are polymers of Formula XXI:

X¹-Y¹-X²-Y²-X³-Y³-X⁴-Y⁴-X⁵-Y⁵-X⁶-Y⁶-X⁷-Y⁷-X⁸-Y⁸-X⁹-Y⁹-X¹⁰

wherein:

X¹ through X¹⁰ are each independently selected sandwich coordinationcompounds;

Y¹ through Y⁹ are independently selected linking groups or linkers; and

X³ through X¹⁰ (and Y³ through Y⁹) may each independently orconsecutively be present or absent (e.g., to provide a polymer ofanywhere from 2 to 10 sandwich coordination compounds)

Articles of manufacture of the present invention may be represented byFormula XXII:

A-X¹(—X^(m+1))_(m)

wherein:

A is a substrate (e.g., a conductor, a semiconductor, an insulator, or acomposite thereof);

m is at least 1 (e.g., 1, 2, or 3 to 10, 20, 50 or 100 or more); and

X¹ through X^(m+1) are sandwich coordination compounds (each of whichmay be the same or different).

Specific examples of articles of manufacture of Formula XXII arearticles of Formula XXIII:

A-X¹-Y¹-X²-Y²-X³-Y³-X⁴-Y⁴-X⁵-Y⁵-X⁶-Y⁶-X⁷-Y⁷-X⁸-Y⁸-X⁹-Y⁹-X¹⁰

wherein:

A is a substrate (e.g., a conductor, a semiconductor, an insulator, or acomposite thereof);

X¹ through X¹⁰ are each independently selected sandwich coordinationcompounds;

Y¹ through Y⁹ are independently selected linking groups or linkers; and

X³ through X¹⁰ (and Y³ through Y⁹) may each independently orconsecutively be present or absent (e.g., to provide a polymer ofanywhere from 2 to 10 sandwich coordination compounds).

E. Memory Devices and Other Articles of Manufacture

Benzazoloporphyrazines of the invention are useful, among other things,for the production of polymers thereof which may be immobilized orcoupled to a substrate and used as light harvesting rods, lightharvesting arrays, and solar cells, as described for example in U.S.Pat. No. 6,407,330 to Lindsey et al. or U.S. Pat. No. 6,420,648 toLindsey. Benzazoloporphyrazines are also useful immobilized to asubstrate for making charge storage molecules and information storagedevices containing the same. Such charge storage molecules andinformation storage devices are known and described in, for example,U.S. Pat. No. 6,208,553 to Gryko et al.; 6,381,169 to Bocian et al.; and6,324,091 to Gryko et al. The compounds can be coupled to substrates toform molecular batteries, molecular capacitors and electrochromicdisplays as described in U.S. Pat. No. 6,777,516 to Li et al. Thebenzazoloporphyrazine may comprise a member of a sandwich coordinationcompound in the information storage molecule, such as described in U.S.Pat. No. 6,212,093 to Li et al., U.S. Pat. No. 6,451,942 to Li et al.,or U.S. Pat. No. 6,777,516 to Li et al.

In one particular embodiment, this invention provides an apparatus forstoring data (e.g., a “storage cell”). The storage cell includes a fixedelectrode electrically coupled to a “storage medium” comprising acompound or polymer as described above, the polymer having a pluralityof different and distinguishable oxidation states where data is storedin the (preferably non-neutral) oxidation states by the addition orwithdrawal of one or more electrons from said storage medium via theelectrically coupled electrode.

In preferred storage cells, the storage medium stores data at a densityof at least one bit, and preferably at a density of at least 2 bits.Thus, preferred storage media have at least 2, and preferably at least4, 8 or 10 or more different and distinguishable oxidation states. Inparticularly preferred embodiments, the bits are all stored innon-neutral oxidation states. In a most preferred embodiment, thedifferent and distinguishable oxidation states of the storage medium canbe set by a voltage difference no greater than about 5 volts, morepreferably no greater than about 2 volts, and most preferably no greaterthan about 1 volt.

The storage medium is electrically coupled to the electrode(s) by any ofa number of convenient methods including, but not limited to, covalentlinkage (direct or through a linker), ionic linkage, non-ionic“bonding”, simple juxtaposition/apposition of the storage medium to theelectrode(s), or simple proximity to the electrode(s) such that,electron tunneling between the medium and the electrode(s) can occur.The storage medium can contain or be juxtaposed to or layered with oneor more dielectric material(s). Preferred dielectric materials areimbedded with counterions (e.g. Nafion® fluoropolymer). The storagecells of this invention are fully amenable to encapsulation (or otherpackaging) and can be provided in a number of forms including, but notlimited to, an integrated circuit or as a component of an integratedcircuit, a non-encapsulated “chip”, etc. In some embodiments, thestorage medium is electronically coupled to a second electrode that is areference electrode. In certain preferred embodiments, the storagemedium is present in a single plane in the device. The apparatus of thisinvention can include the storage medium present at a multiplicity ofstorage locations, and in certain configurations, each storage locationand associated electrode(s) forms a separate storage cell. The storagemedium may be present on a single plane in the device (in a twodimensional or sheet-like device) or on multiple planes in the device(in a three-dimensional device). Virtually any number (e.g., 16, 32, 64,128, 512, 1024, 4096, etc.) of storage locations and storage cells canbe provided in the device. Each storage location can be addressed by asingle electrode or by two or more electrodes. In other embodiments, asingle electrode can address multiple storage locations and/or multiplestorage cells.

In preferred embodiments, one or more of the electrode(s) is connectedto a voltage source (e.g. output of an integrated circuit, power supply,potentiostat, microprocessor (CPU), etc.) that can provide avoltage/signal for writing, reading, or refreshing the storage cell(s).One or more of the electrode(s) is preferably connected to a device(e.g., a voltammetric device, an amperometric device, a potentiometricdevice, etc.) to read the oxidation state of said storage medium. Inparticularly preferred embodiments, the device is a sinusoidalvoltammeter. Various signal processing methods can be provided tofacilitate readout in the time domain or in the frequency domain. Thus,in some embodiments, the readout device provides a Fourier transform (orother frequency analysis) of the output signal from said electrode. Incertain preferred embodiments, the device refreshes the oxidation stateof said storage medium after reading said oxidation state.

Particularly preferred methods and/or devices of this invention utilizea “fixed” electrode. Thus, in one embodiment, methods and/or devices inwhich the electrode(s) are moveable (e.g. one or more electrodes is a“recording head”, the tip of a scanning tunneling microscope (STM), thetip of an atomic force microscope (AFM), or other forms in which theelectrode is movable with respect to the storage medium) are excluded.Similarly in certain embodiments, methods and/or devices and/or storagemedia, in which the storage molecules are responsive to light and/or inwhich the oxidation state of a storage molecule is set by exposure tolight are excluded.

In another embodiment, this invention provides an information storagemedium. The information storage medium can be used to assemble storagecells and/or the various memory devices described herein. In a preferredembodiment the storage medium comprises one or more different storagemolecules including a compound as described herein. When differentspecies of storage molecule are present, the oxidation state(s) of eachspecies is preferably different from and distinguishable from theoxidation state(s) of the other species of storage molecule comprisingthe storage medium.

This invention also provides methods of storing data. The methodsinvolve i) providing an apparatus, e.g., comprising one or more storagecells as described herein; and ii) applying a voltage to the electrodeat sufficient current to set an oxidation state of said storage medium(the storage medium comprising one or more storage cells). In preferredembodiments, the voltage range is less than about 5 volts, morepreferably less than about 2 volts, and most preferably less than about1 or less than about 0.5 volts. The voltage can be the output of anyconvenient voltage source (e.g. output of an integrated circuit, powersupply, logic gate, potentiostat, microprocessor (CPU), etc.) that canprovide a voltage/signal for writing, reading, or refreshing the storagecell(s).

The method can further involve detecting the oxidation state of thestorage medium and thereby reading out the data stored therein. Thedetection (read) can optionally involve refreshing the oxidation stateof the storage medium. The read (detecting) can involve analyzing areadout signal in the time or frequency domain and can thus involveperforming a Fourier transform on the readout signal. The detection canbe by any of a variety of methods including, but not limited to avoltammetric method.

This invention additionally provides the memory devices of thisinvention (e.g. memory cells) in a computer system. In addition computersystems utilizing the memory devices of this invention are provided.Preferred computer systems include a central processing unit, a display,a selector device, and a memory device comprising the storage devices(e.g. storage cells) of this invention.

The present invention is explained further in the following non-limitingExamples. As used herein, DBU=1,8-diazabicyclo[5.4.0]undec-7-ene;DBN=1,5-diazabicyclo[4.3.0]non-5-ene; and NMP=N-methylpyrrolidinone.

Examples 1-30 Synthesis of a trans-A₂B₂ phthalocyanine motif for thepreparation of rod-like phthalocyanine polymers

The inherent geometry of phthalocyanines is an important considerationin approaches to linear phthalocyanine polymers. In FIG. 1, two possibleABAB phthalocyanines are shown, having 2,16- and 2,17-substitutionpatterns. The substituents of the 2,17 isomer are at a 120° angle withrespect to each other, whereas those of the 2,16-isomer are parallel butnot collinear. This is the result of the fact that each of theperipheral substituents shown in these structures is offset with respectto one of the central N-N axes by a 30° angle (see FIG. 1 for definitionof the N-N axis). A polymer prepared from a mixture of these isomerscould not be expected to afford a linear alignment. Even a polymerproduced solely from the 2,17-isomer would be unlikely to hold a 180°alignment over long range due to rotation about the bonds between thephthalocyanines and their linkages.

A modification of the core pigment scaffold such that substituents arecollinear with the N-N axes of the macrocycles should result in amonomer suitable for rod-like polymers. Such an architecture can beachieved with phthalocyanines bearing five-membered outer rings, eitherin place of the standard benzo rings, or by extra-annulation. Since afive-membered all-carbon ring would break the aromaticity of themacrocycle, the outermost ring must be heterocyclic. There are reportedsyntheses for phthalocyanines bearing diverse five-membered heterocyclicouter rings (Stuzhin, P. A.; Ercolani, C. In The Porphyrin Handbook,Kadish, K. M., Smith, K. M., Guilard, R., Eds., Academic Press: SanDiego, 2003; Vol. 15, pp 263-364). Some are obtained by the use ofheterocyclic building blocks, whereas others are achieved by peripheralmodification of substituted phthalocyanines. Those that permitsubstitution at the outermost position include pyrrole, indole,imidazole, and thiophene. From this shortened list, the extra-annulatedimidazole appeared the most accessible in teens of numbers and types ofsynthetic steps. Phthalocyanines bearing this motif have been previouslytermed imidazophthalocyanines, as well as benzimidazoloporphyrazines(Note that a tetrabenzoporphyrazine is synonymous with aphthalocyanine.) This report uses the term benzimidazoporphyrazines, aslight abbreviation of the previous moniker, and still unambiguous withrespect to the motif.

These examples describe the synthesis of a linear, trans-substitutedphthalocyanine analogue, based on the benzimidazoporphyrazine scaffold.The development of new synthetic methodology forbenzimidazoporphyrazines (BzImPAs) is presented as a stepping-stonetoward the desired trans-BzImPA(s). The structural properties andphotochemical behavior have been compared with those of well-knownphthalocyanines.

Synthesis. All of the published reports of benzimidazoporphyrazines haveemployed 5,6-dicyanobenzimidazoles as the key building blocks ((Pardo,C.; Yuste, M.; Elguero, J. J. Porphyrins Phthalocyanines 2000, 4,505-509; (a) Kudrik, E. V.; Shaposhnikov, G. P. Mendeleev Commun. 1999,85-86. (b) Kudrik, E. V.; Shaposhnikov, G. P.; Balakirev, A. E. Russ. J.Gen. Chem. 1999, 69, 1321-1324. (c) Balakirev, A. E.; Kudrik, E. V.;Shaposhnikov, G. P. Russ. J. Gen. Chem. 2002, 72, 1616-1619)). Kudrikand coworkers showed the utility of dicyanophenylenediamine 3 (Scheme 1)as a precursor to 2-alkyl-5,6-dicyanobenzimidazoles. Their synthesis of3 required seven steps, with an overall yield of ˜7% (see:(a)Zharnikova, M. A.; Balakirev, A. E.; Maizlish, V. E.; Kudrik, E. V.;Shaposhnikov, G. P. Russ. J. Gen. Chem. 1999, 69, 1870-1871. (b)Shishkina, O. V.; Maizlish, V. E.; Shaposhnikov, G. P.; Lyubimtsev, A.V.; Smirnov, R. P.; Baran'ski, A. Russ, J. Gen. Chem. 1997, 67, 842-845.(c) Elvidge, J. A.; Golden, J. H.; Linstead, R. P. J. Chem. Soc. 1957,2466-2469; Levy, L. F.; Stephen, H. J. Chem. Soc. 1931, 79-82)).

The preparation of 3 by Mitzel and coworkers, with a 14% yield over foursteps, is the best reported route to date (Mitzel, F.; Fitzgerald, S.;Beeby, A.; Faust, R. Chem. Eur. J. 2003, 9, 1233-1241; Cheeseman, G. W.H. J. Chem. Soc. 1962, 1170-1176; Acheson, R. M. J. Chem. Soc. 1956,4731-4735; Elderfield, R. C.; Meyer, V. B. J. Am. Chem. Soc. 1954,1887-1891; Mørkved, E. H.; Neset, S. M.; Bjørlo, O.; Kjøsen, H.;Hvistendahl, G.; Mo, F. Acta Chem. Scand. 1995, 49, 658-662). Scheme 1shows a new synthesis of 3, with a 14% yield over three steps.

The iodination of dinitrobenzene uses I₃ ⁺, formed by mixture of iodinewith oleum (Arotsky, J.; Butler, R.; Darby, A. C. J. Chem. Soc. (C)1970, 1480-1485). The reconstitution of I₂ as a product of the ensuingiodination reaction allows the I₃ ⁺ intermediate to reform continuously,and thus makes atom-economic use of the halogen starting material.However, even this efficiency does not explain the original reportedyield of 56% for diiodination when using only a half-equivalent of I₂.Attempts to repeat the reaction as reported consistently gave yields of19-20%. The yield was improved to 39% by lowering the temperature of thereaction from 180° C. to 120° C., shortening the time to 75 min, andincreasing the iodine to the stoichiometric requirement (1 equiv of I₂for diiodination). The low yield of the reaction is compensated by itsamenity to high scale (see Experimental Section). The reduction of 1 tothe corresponding diamino compound 2 using Sn/HCl has been reported byWhitesides and coworkers, although no specific procedure or yield wasprovided (Schwiebert K. E.; Chin, D. N.; MacDonald, J. C.; Whitesides,G. M. J. Am. Chem. Soc. 1996, 118, 4018-4029). The use of Fe/HCl gavethe compound in 66% yield and avoids the voluminous tin salts which aretypical of Sn reductions. The diamine 2 complexes readily with the ironsalts formed from the reaction, requiring treatment of the hot mixturewith an aqueous solution of EDTA to recover the product. The cyanationof 2 proceeds at lower temperature (120 vs. 140° C.) more quickly (3 vs.15 h) and in greater yield (55 vs. 25%) than for the correspondingdibromophenylenediamine (Mitzel, F.; Fitzgerald, S.; Beeby, A.; Faust,R. Chem. Eur. J. 2003, 9, 1233-1241). Complexation of the product withthe copper salts left over at the end of the reaction is again avoidedby treatment of the hot crude mixture with an aqueous solution of EDTA.

Dicyanobenzimidazoles have previously been prepared from 3 andcarboxylic acids (Kudrik, E. V.; Shaposhnikov, G. P. Mendeleev Commun.1999, 85-86; Kudrik, E. V.; Shaposhnikov, G. P.; Balakirev, A. E. Russ.J. Gen. Chem. 1999, 69, 1321-1324; Balakirev, A. E.; Kudrik, E. V.;Shaposhnikov, G. P. Russ. J. Gen. Chem. 2002, 72, 1616-1619). However,in these reports, the carboxylic acids have been of low molecular weight(e.g., formic to hexanoic acid) and were used neat, thereby serving asreagent, solvent, and Brönsted acid catalyst. In contrast, benzimidazolesyntheses using substituted benzoic acids with o-phenylenediamine havetypically employed strong hygroscopic acids such as conc. HCl andpolyphosphoric acid as the solvent/catalyst (a) Kudrik, E. V.;Shaposhnikov, G. P. Mendeleev Commun. 1999, 85-86. (b) Kudrik, E. V.;Shaposhnikov, G. P.; Balakirev, A. E. Russ. J. Gen. Chem. 1999, 69,1321-1324. (c) Balakirev, A. E.; Kudrik, E. V.; Shaposhnikov, G. P.Russ. J. Gen. Chem. 2002, 72, 1616-1619). The oxidative cyclizationyielding benzimidazoles from phenylenediamines and aldehydes is a mildertechnique. Originally developed by Weidenhagen using Cu(OAc)₂(Weidenhagen, R. Chem. Ber. 1936, 69, 2263-2272; Weidenhagen, R.;Weedon, U. Chem. Ber. 1938, 71, 2347-2360), this method has evolved inrecent years to the more environmentally benign use of O₂, with FeCl₃ asa catalytic oxidant ((a) Weidenhagen, R. Chem. Ber. 1936, 69, 2263-2272;Weidenhagen, R.; Weedon, U. Chem. Ber. 1938, 71, 2347-2360; Singh, M.P.; Sasmal, S.; Lu, W.; Chatterjee, M. N. Synthesis 2000, 1380-1390).Scheme 2 shows the oxidative cyclizations using 3 and selected aldehydes4a-d. Yields of 58% and 81% were obtained for benzimidazoles 5a and 5d,respectively. The reactions required longer times than those previouslyreported, perhaps due to the more electron-poor quality of 3 compared too-phenylenediamine. Benzimidazole 5d was also prepared directly from 2,taking advantage of the copper salts left over from the cyanationreaction (Scheme 1), by adding aldehyde 4c and bubbling O₂ through thecrude reaction mixture containing 3. This procedure was considerablyfaster than the FeCl₃ method, due to the large quantity of copper saltspresent, and gave 5d in 41% yield. It was however, not successful for5a. Due to the poor solubility of compounds 5b and 5c, the cyclizationreaction mixture was carried forward directly to alkylation at the1-position, giving 6b and 6c.

Scheme 2

Compound R Yield (from 3) 6a

76% 6b

44% 6c

50% 6d

35%

Alkylation of the 1-position of these dicyanobenzimidazoles with therelatively small propyl group was predicated on the intent to use theresulting benzimidazoporphyrazines as components in materials where themacrocycles would be closely packed. Larger alkyl groups, althoughperhaps helpful for the solubility of the benzimidazoporphyrazines,would prohibit the close packing of the macrocycles. Benzimidazoles 5aand 5d proved unreactive to iodopropane in the absence of a base, evenat elevated temperature. Deprotonation could be effected with DBU, andsubsequent alkylation with iodopropane (bp 101° C.) succeeds at 80° C.in acetonitrile or NMP (N-methylpyrrolidinone). The initial yield of thealkylation reaction is low, but by using successive rounds of additionof the base and electrophile in the reaction, acceptable yields wereobtained. The use of excess base did not raise the yield of thereaction. Propyl-dicyanobenzimidazoles 6a-d were obtained in 35-76%yield from diamine 3. The swallowtail benzimidazole 5a gave betterresults in the alkylation reaction (94%) compared to the2-arylbenzimidazoles, suggesting some influence of the 2-substituent onthe basicity/nucleophilicity of the benzimidazole.

The swallowtail- and phenyl-benzimidazoles 6a and 6b were chosen asbenchmark motifs for 2-alkyl- and 2-aryl-5,6-benzimidazoporphyrazines,respectively. In principle, a wide variety of aldehyde-bearing groupscan be installed at the 2-position. This versatility is limited by thestability of a given aldehyde-bearing group under the conditions of theoxidative cyclization and alkylation reactions. Groups that mightinterfere with or be affected by these two steps, such as ferrocenyl orpyridyl, can be transformed to dicyanobenzimidazoles by cross-couplingto the p-iodophenyl-benzimidazole 6c. The protectedethynylphenyl-benzimidazole 6d was prepared as a building block fortrans-diethynyl-benzimidazoporphyrazines.

The previous reports of A₄-type benzimidazoporphyrazines report UV-Visabsorption spectra in DMF and sulfuric acid (Pardo, supra; Kudrik,supra, Balakirev, supra). Benzimidazoporphyrazines 7 and 8 (Scheme 3),as well as the corresponding zinc and magnesium chelates, were preparedto investigate the photochemical properties of these macrocycles (∈,λ_(abs), λ_(em), Φ_(f)) in common organic solvents. This allows acomparison of the effects of the extra-annular imidazole ring with thecorresponding benzo rings of naphthalocyanine (vide infra), without thecomplicating effects of low symmetry in the target trans-substitutedmacrocycle. The yields of the DBU-mediated reactions of 6a increaseaccording to the presence and type of metal salt in the order Fb<Mg<Zn,in accord with known results for phthalocyanine formation using DBU withand without metal salts (Tomoda, H.; Saito, S.; Ogawa, S.; Shiraishi, S.Chem. Lett. 1980, 1277-1280; Tomoda, H.; Saito, S.; Shiraishi, S. Chem.Lett. 1983, 313-316). The corresponding reactions with 6b do show animprovement in the yields for the metallo-derivatives compared to thefree base, but the DBU-mediated reaction was slightly better than thatusing lithium pentoxide, and the yields of Mg-8 and Zn-8 are withinexperimental variation. The ¹H NMR spectrum of Fb-8 shows the usualevidence of the aromatic ring current, with the core protons found at−3.13 ppm, whereas in Fb-7 the core protons are found at 0.30-0.50 ppm.Whether this latter result is due to a steric or electronic effect isnot known. The general structure shown in Scheme 3 depicts a macrocyclehave C_(4h) symmetry, but the A₄ benzimidazoporphyrazines can have up tofour regioisomers resulting from the placement of the propyl groups. Asa result, the ¹H NMR spectra of the zinc and free base fours of 7 and 8exhibited broad signals for most of the expected resonances. However,the ¹H NMR signatures for Mg-7 and Mg-8 were far less complex,indicating a possibly monodisperse product. The effect of metaltemplating on the distribution of regioisomers in phthalocyanine-formingreactions has been previously detailed (Rager, C.; Schmid, G.; Hanack,M. Chem. Eur. J. 1999, 5, 280-288). All of the A₄benzimidazoporphyrazines are green in solid form as well as in solution.

Scheme 3

Yield (%) Com- Fb Fb pound R (DBU) (Li) Mg Zn 7

11 49 27 46 8

38 28 65 62

Initial attempts to prepare a trans-diethynyl-benzimidazoporphyrazinefrom macrocyclization of mixtures of dicyanobenzimidazoles were plaguedby the inseparability of the resulting products. Analysis of the productmixture from the reaction of 6a and 6d (Scheme 4) by laser desorptionmass spectrometry (LD-MS) indicated that all possible products had beenformed, but no successful separation could be effected by eitheradsorption chromatography (silica or alumina) or size exclusionchromatography. The same circumstances were encountered for thereaction, between 6d and diheptylphthalonitrile 10 (Scheme 4). Thereaction of 6d with dicyanobenzene (Scheme 5) was more successful,allowing the separation of the smaller macrocyclic products (A₄, A₃B,and A₂B₂) from the larger ones (AB₃ and B₄) by size exclusionchromatography. The smaller macrocycles were then further separated byadsorption chromatography. The larger macrocycles were not isolated.Compound 6b appeared to be slightly more reactive than1,2-dicyanobenzene, and a 1:1 ratio of the two reactants (respectively)gave a product mixture favoring the AB₃ and B₄ products. A correspondingratio of 1:1.5 gave a more even mixture of the possible products. Therecovered samples of the trans-diethynyl-benzimidazoporphyrazine Zn-13and the cis-isomer Zn-12 displayed similar ¹H NMR spectra, but wereeasily distinguished by their respective UV-Vis absorption spectra (videinfra). Zn-11 was easily separated in the initial size exclusion column.This compound is a blue solid, but takes on a blue-green color insolution. The A₂B₂ compounds are also blue solids, but appear green insolution.

Scheme 5

Zn-11 + other Pc's Pc Compound Yield A₄ Zn-10  4% A₃B Zn-11 22% A₂B₂-cisZn-12 14% A₂B₂-trans Zn-13  1%

Dicyanobenzimidazole 6d was transformed into the correspondingdiiminoisoindoline

14 in 76% yield using a well-known procedure (Scheme 6) (Brach, P. J.;Grammatica, S. I.; Ossanna, O. A.; Weinberger, L. J. Heterocyc. Chem.1970, 7, 1403-1405). The product did not fully crystallize from thereaction as is usually reported, but the quantity of recovered solidcould be amplified by concentrating the mixture using a stream of argon.The crystals obtained were greenish-white needles that turned deep greenupon melting. The melted sample was recovered from the capillary and wasfound to exhibit a UV-Vis absorption profile analogous to that of Fb-8.

Diiminoisoindoline 14 was reacted with boron-subphthalocyanine (15) toprepare the A₃B compound Fb-11 (Scheme 6). Due to the reactivity of 14,the subPc 15 had to be employed at four times the stoichiometric ratioin order to suppress the formation of products having more than onebenzimidazole moiety. The reaction yield was highest when conducted at100° C. Higher temperatures gave the product more quicldy but in loweryield, whereas lower temperatures were ineffective. Fb-11 exhibits poorsolubility, but is marginally more soluble than the large quantity ofunsubstituted phthalocyanine that is also formed. The desired productcould be largely separated from the unsubstituted phthalocyanine bySoxhlet extraction of the solid residue of the reaction usingchloroform, followed by size-exclusion chromatography. Although theyield is modest (25%), the alternative route to Fb-11 would be thedemetalation of Zn-11, which is not possible under mild conditions.(Zinc-porphyrins can be demetalated in the presence of TFA at roomtemperature, but this is ineffective for zinc phthalocyanines.) There isno published report of the demetalation of a zinc-phthalocyanine. Fb-11was colored very similarly to Zn-11, blue in solid form and slightlymore greenish blue in solution.

The trans-diethynyl-benzimidazoporphyrazine Fb-13 was prepared in 9%yield by cross-condensation of diiminoisoindoline 14 withtrichloroisoindolenine 16 (Scheme 7), following the procedure reportedby Young and Onyebuagu (Young, J. G.; Onyebuagu, W. J. Org. Chem. 1990,55, 2155-2159). A trace quantity of an AB₃ byproduct was formed in thereaction, as previously observed (Stihler, P.; Hauschel, B.; Hanack, M.Chem. Ber. 1997, 130, 801-806). The yield of the trans-A₂B₂ productdropped to 4% when ZnCl₂ was used as a templating agent in the reaction.The compound Zn-13 was more accessible by metalation of Fb-13 usingZn(OAc)₂.2H₂O. There are two possible regioisomers of the trans-A₂B₂structure, of C₂, and C_(2h) symmetries, owing to the position of therespective N_(imidazo) substituents. For Fb-13 these regioisomers werenot separable by chromatography on silica gel. The ¹H NMR spectra of theisolated sample of Fb-13 had duplicate signals for each expectedresonance, including the protons within the macrocycle. This result issimilar to the ¹H NMR spectra for the free base and zinc metalated A₄benzimidazoporphyrazines. Compound Fb-8 has a slightly broadened signalfor the inner protons, but not the twinned peaks that are seen forFb-13. Hanack and coworkers attributed the split appearance of the innerproton resonance to the different environments encountered by the NHprotons in the tautomers of their trans-A₂B₂ structure (Stihler, P.;Hauschel, B.; Hanack, M. Chem. Ber. 1997, 130, 801-806). A variabletemperature ¹H NMR experiment in d₈-THF showed that the signals for thevarious duplicated resonances of Fb-13 did approach one another at hightemperatures (up to 55° C.), but the signals never merged, and the usualbroadening associated with exchange-equilibrium behavior was notobserved. Given the rather low temperature limit of the solvent, thisresult is not conclusive as to the origin of the twinned resonances.

Scheme 7

The ¹H NMR spectrum of a sample of Zn-13 having both regioisomers wasfar less complex than the corresponding signature of the free basecompound. Only the aromatic region showed more complexity than would beexpected for a monodisperse sample. Although this supports thehypothesis that the duplicate set of signals observed for Fb-13 is theresult of tautomerism, the simplicity of the spectrum of Zn-13 can alsobe interpreted as the coincidental overlapping of several signatures.Fortunately, the regioisomers of Zn-13 were separable by chromatographyon silica gel, and exhibited distinct patterns in the aromatic region ofthe ¹H NMR spectrum, enabling assignment. The first eluting species,Zn-13a, exhibits an ABCD splitting pattern for the protons on the benzorings, consistent with the assignment of C_(2h) symmetry. The secondeluting species, Zn-13b, shows multiplets that resemble typical AA′BB′splitting patterns, corresponding to the structure assigned to C_(2v)symmetry. COSY NMR analyses were performed to confirm the couplingpatterns that support these assignments of the regioisomers. As with theA₂B₂ products from the reaction of 6d with dicyanobenzene, all of thetrans-A₂B₂ compounds were blue in solid form but deeply green insolution.

The deprotection of Zn-13a and Zn-13b proceeded smoothly using TBAF indichloromethane, but the compounds proved to be surprisingly polarduring chromatography (Scheme 8).

Loss of the triisopropylsilyl groups also adversely affected thesolubility of the resulting diethynyl compounds. Whereas Zn-13a/b aresoluble in chlorinated solvents and very soluble in THF, the productsZn-17a/b slowly precipitated from the eluent upon exiting thechromatography column, and are then only weakly soluble in chlorinatedsolvents, and moderately soluble in THF. This low solubility makes theprospect of chemical (e.g., Pd mediated) polymerization of the diethynylmonomer more challenging. Other polymerization options exist, such asthe thermal polymerization of diethynyl porphyrins (Liu, Z.; Schmidt,I.; Thamyongkit, P.; Loewe, R. S.; Syomin, D.; Diers, J. R.; Zhao, Q.;Misra, V.; Lindsey, J. S., Bocian, D. F. Chem. Mater. 2005, in press)

The procedures developed for this route typically gave moderate to lowyields, but are each amenable to higher scale. The biggest losses areincurred at the initial synthesis of compound 1 and thecross-condensation synthesis of Fb-13. The quantities of the isolateddiethynyl-trans-benzimidazoporphyrazines are small (<10 mg), butsufficient for their full characterization and testing in exploratorypolymerizations.

Photochemistry. The absorption and emission spectra of compounds Fb-7,Zn-7, and Mg-7 are shown in FIG. 2. The spectra for thephenyl-substituted M-8 series are closely matching to those of the alkylseries M-7, but are red-shifted by 2-4 nm (Table 1). The generalappearance of the spectra is typical of phthalocyanines, with broad Bbands in the 300-400 nm region, and sharper Q bands providing strongabsorbance in the red/near-IR portion of the spectrum. Of all thebenzimidazoporphyrazines in this study, only Fb-8 does not obey theBeer-Lambert law. For the others, no significant change is observed inthe UV-V is absorbance profile between solutions having maximalabsorbance in the range 0.02-2.0 absorbance units. Fb-8 showed a 15%decrease in the ratio of the B band to the Q band between solutions at0.02 and 2.0 absorbance units. The extinction coefficients are somewhathigher than the reported values for unsubstituted phthalocyanines andeven the more soluble tetra-tert-butylphthalocyanines, but this maysimply be an effect of the narrowness of the Q band maxima for theBzImPAs ((a) data for (t-Bu)₄H₂Pc and (t-Bu)₄MgPc: Teuchner, K.;Pfarrherr, A.; Stiel, H.; Freyer, W.; Leupold, D. Photochem. Photobiol.1993, 57, 465-471. (b) additional data for (t-Bu)₄MgPc: Freyer, W.;Dähne, S.; Minh, L. Q.; Teuchner, K. Z. Chem. 1986, 26, 334-336. (c)data for (t-Bu)₄ZnPc: Tran-Thi, T.-H.; Desforge, C.; Thiec, C.; Gaspard,S. J. Phys. Chem. 1989, 93, 1226-1233).

The Q bands of the A₄ BzImPAs are red-shifted by ˜35-50 nm compared tothe corresponding free base or metallophthalocyanines. The Q band maximafor various phthalocyanine species in THF are as follows: zincphthalocyanine (ZnPc, 665 nm), ⁴⁵Zn-7 (713 nm), and zincnaphthalocyanine (ZnNc, 756 nm)(Kobayashi, N.; Mack, J.; Ishii, K.;Stillman, M. J. Inorg. Chem. 2002, 41, 5350-5363). Thus, the differencebetween the excited-state energy gap of ZnPc and ZnNc is 1820 cm⁻¹; theexcited-state energy gap of Zn-7 is 1015 cm⁻¹ greater than that of ZnPc,and 805 cm⁻¹ less than that of ZnNc. This is not surprising given therelative extent of π-conjugation in each species: ZnPc has a total of42π electrons, spread over 36 nuclei, while ZnNc has 54π electrons thatare spread out over 48 nuclei; the π-system of Zn-7 has the same numberof electrons as ZnNc, but four fewer nuclei. This translates to fourfewer molecular orbitals via the LCAO formalism, and explains why theBzImPAs are blue-shifted compared to naphthalocyanines. Anotherdistinction of the imidazole annulation is that the moderate red-shiftof the phthalocyanine electronic transitions comes without any sacrificein the fluorescence quantum yield. Whereas the Φ_(f) of ZuNc (0.13) isreduced from that of ZnPc (0.32), the Φ_(f) of Zn-7 is higher (0.47).

The lower symmetry of free base macrocycles Fb-11 (A₃B) and Fb-13(trans-A₂B₂) results in very different behavior from the A₄ BzImPAs.FIG. 3 shows the absorption and emission profiles of the A₃B andtrans-A₂B₂ compounds. The Q band maxima are more complex, the Q bandintensity is dropped to roughly the same as the B band, and thefluorescence behavior shows dependence on the wavelength of excitation.The altered Q/B ratio is not the result of aggregation, as no differencewas observed in the absorption profile between solutions having maximalabsorptions of 0.02 and 2.0 absorbance units (a 100-fold change inconcentration).

TABLE 1 Photochemical data for benzimidazoporphyrazines. B band Q bandsλ_(abs) (nm) λ_(abs) (nm) Compound [ε_(Log 10)] [ε_(Log 10)] Q/B^(a)λ_(em)(nm) Φ_(f) ^(b) Fb-7 376 [4.96] 713 [5.37], 3.2 742 0.59 738[5.47] Fb-8 382 [4.96] 718 [5.31], 2.6 744 0.70 740 [5.38] Fb-11 337[4.89] 669 [4.98], 1.2 700, 714^(c) 0.68 695 [4.98] Fb-13 340 [5.13] 662[4.99], 1.1 711, 739^(c) 0.66 681 [4.99] 703 [5.18], 732 [4.94] Zn-7 357[5.03] 713 [5.58] 3.6 720 0.47 Zn-8 357 [5.08] 717 [5.59] 3.2 724 0.43Zn-11 340 [5.10] 674 [5.43] 2.2 692 0.47 Zn-12 340 [4.95] 693 [5.31] 2.3701 0.44 Zn-13a 338 [5.12] 679 [5.37], 1.75 717 0.32 709 [5.21] Zn-13b338 [5.11] 679 [5.36], 1.78 717 0.26 709 [5.19] Mg-7 363 [5.14] 713[5.61] 3.0 720 0.69 Mg-8 364 [5.12] 717 [5.53] 2.6 724 0.84 ^(a)Ratiosof intensities were calculated from absorbance data. Q value was chosenfrom the most intense Q band for a given compound. ^(b)The method forquantum yield determination is described in the Experimental Section.^(c)The fluorescence profile of the sample was dependent upon thewavelength of excitation.

There are two transition dipole moments, one along the short axis of themolecule and one along the long axis of the molecule. In addition, forthe free base A₃B and trans-A₂B₂ BzImPAs, tautomerism of the inner NHprotons can result in either N—N or NH—NH along the short axis, andNH—NH or N—N along the long axis. (By contrast, the standard free basephthalocyanine system also two distinct transition dipole moments owingto the N—N and NH—NH axes. The two transition dipole moments, normallylabeled as Q_(x) and Q_(y), respectively, give rise to the two sets ofpeaks normally observed.) For the free base A₃B and trans-A₂B₂ BzImPAs,the tautomerism of the core protons may give result in twophotochemically distinct species, as the Q_(x) and Q_(y) dipoles willeach give rise to distinct electronic transitions depending on theirplacement on the short or elongated axis of the macrocycle.

This hypothesis is supported by the fluorescence behavior of Fb-11 andFb-13: each compound appears to have two strong fluorescence maxima andmore than two accompanying vibronic bands at longer wavelengths. The twotautomers of a given low symmetry free base macrocycle may each beresponsible for one emission maximum and accompanying vibronic bands.Thus the complex absorption profiles are not indicative of a single setof electronic transitions, but rather are each an overlay of the bandsdue to two photochemically distinct species. If these complex absorptionand emission profiles were indeed the result of individual photochemicalspecies, then the compounds would be in violation of Kasha's rule, whichstates that excited chromophores must always pass through the samelowest singlet excited state before returning to the ground state.

The zinc chelates Zn-11, Zn-12, and Zn-13, each show a single emissionmaximum. For Zn-12 (cis-A₂B₂ architecture) this is no surprise, as thetwo axes of the phthalocyanine are identical with respect to theirextent of annulation. Zn-13 (trans-A₂B₂) shows the type of double Q bandmanifold normally expected for a free base BzImPA, due to the pronounceddifference in the length of the two axes. Zn-11 has a tall shoulder onthe longer wavelength side of the band, and may have two distincttransition dipole moments as in Zn-13, but the two dipole moments mayoverlap so extensively as to appear to be one band. The two regioisomersof Zn-13, of C_(2h) and C_(2v) symmetry, show almost identical spectra.The extinction coefficients of Zn-13b are minutely smaller than those ofZn-13a, and the ratio of the intensity of the two Q bands to one anotherin Zn-13a is slightly lower (3%) than the corresponding ratio of Q bandsin Zn-13b. The fluorescence quantum yields are slightly different, butboth are still in an acceptable range for zinc phthalocyanine-typecompounds. These two diethynyl constructs are essentially equivalent andtheir deprotected derivatives Zn-17a and Zn-17b should be of equalutility as polymerizable extra-annulated phthalocyanines.

General. ¹H (400 MHz) and ¹³C (75 MHz) NMR spectra were obtained inCDCl₃ unless noted otherwise. Silica gel (Scientific Adsorbents, 40 μmaverage particle size) was used for column chromatography. AnhydrousCH₂Cl₂ was purchased from Aldrich. Aldehydes 4b and 4c were purchasedfrom Aldrich and used as received. All other chemicals were reagentgrade and were used as received. Benzimidazoles 5b and 5c were notisolated but were carried forward to the corresponding products 6b and6c. Photochemical data were measured using THF as solvent. Fluorescencequantum yields were measured by comparison totetra-tert-butylphthalocyanine, which was itself measured in both THFand CHCl₃ set at Φ_(f)=0.70 in THF (by comparison to the reported Φ_(f)of 0.77 for tetra-tert-butylphthalocyanine in CHCl₃ with correction forthe indices of refraction of the different samples).

Example 1

Noncommercial Compounds: Compounds 4a (Kato, M.; Komoda, K.; Namera, A.;Sakai, Y.; Okada, S.; Yamada, A.; Yokoyama, K.; Migita, E.; Minobe, Y.;Tani, T. Chem. Pharm. Bull. 1997, 45, 1767-1776), 4d (Rao, P. D.;Dhanalekshmi, S.; Littler, B. J.; Lindsey, J. S. J. Org. Chem. 2000, 65,7323-7344), 9 (Nishi, H.; Azuma, N.; Kitahara, K. J. Heterocyclic Chem.1992, 29, 475-477; Hanack, M.; Haisch, P.; Lehmann, H.; Subramanian, L.R. Synthesis 1993, 387-390), 15 (Claessens C. G.; Gonzalez-Rodriguez D.;del Rey B.; Torres T.; Mark G.; Schuchmann H. P.; von Sonntag C.;MacDonald J. G.; Nohr R. S. Eur. J. Org. Chem. 2003, 14, 2547-2551), and16 (Farbenfabriken Bayer, U.S. Pat. No. 2,701,252; Feb. 1, 1955) wereprepared according to the literature.

Example 2

1,2-Diiodo-4,5-dinitrobenzene (1). A three-necked 100 mL round-bottomflask was charged with oleum (38 mL of a 20% solution, 0.18 mol SO₃),and a magnetic stirring bar. The flask was fitted with a condenser and abubbler and the spare necks were closed with glass stoppers. The flaskwas placed in an oil bath heated to 120° C. Iodine (6.86 g, 27.0 mmol)was added to the flask. After 20 min, o-dinitrobenzene (4.54 g, 27.0mmol) was added to the reaction vessel, and the reaction was heated for75 min, and then removed from heat and immediately poured into a 1 Lconical flask filled with ice. The crude mixture was quenched with NaOHpellets until it was slightly alkaline to pH paper, with more ice addedto keep the mixture cold. The mixture was then filtered through filterpaper and the filtrate was extracted with CHCl₃. The organic layer ofthe extraction was washed with aqueous Na₂S₂O₅, water, and brine, driedover Na₂SO₄, filtered, and concentrated to dryness. The dark brownfilter cake was stirred with 200 mL of hot water to which Na₂S₂O₅ wasadded until no further bubbling was observed. The mixture was thenfiltered and the filtrate was discarded. The filter cake and the residuefrom the extraction were recrystallized (EtOH/water) yielding dark browncrystals (4.47 g, 39%): mp 183-184° C.; ¹H NMR δ 8.31 (s, 2H); ¹³C NMR δ114.6, 134.8; Anal. Calcd for C₆H₂I₂N₂O₄: C, 17.16; H, 0.48; N, 6.67;Found: C, 17.44; H, 0.41, 6.61.

Scale-up: The above procedure was followed with the following quantitiesof reagents: oleum (200 mL), iodine (37.80 g), o-dinitrobenzene (25.0g). To quench the large volume of SO₂ produced by the reaction, theevolved gas was bubbled through a solution of aqueous NaOH (5 M, 1 L),which was later used to quench the acidic crude reaction mixture overice, along with an additional 125 g of NaOH, followed by Na₂S₂O₅ (18.5g). The CHCl₃ extraction of the initial crude filtrate was omitted.Yield: 32%. Characterization data were consistent with the smaller scalereaction.

Example 3

1,2-Diamino-4,5-diiodobenzene (2). Following a literature procedure, asample of 1 (17.42 g, 41.5 mmol) and a magnetic stirring bar were addedto a 500 mL conical flask fitted with a jacketed condenser. EtOH (95%,150 mL) and conc. aqueous HCl (68.6 mL, 0.83 mol) were added, and themixture was stirred and heated to boiling. Fe (18.59 g, 0.332 mol) wasadded in portions, resulting in foaming of the mixture and acceleratedrefluxing of the EtOH, which would subside within a few minutes of eachaddition. The reaction was heated for an additional 45 min beyond thefinal addition of Fe. A hot solution of EDTA (156 g, 0.411 mol, in 300mL H₂O) was added to the reaction mixture, and KOH pellets were addeduntil the solution was alkaline to pH paper. The hot mixture wasextracted twice with ethyl acetate and the extracts were combined,washed with water, followed by brine, dried over Na₂SO₄, filtered andconcentrated to dryness. The residue was recrystallized (EtOH/water),giving tan needles (9.92 g, 66%): mp 135-136° C.; ¹H NMR (d₈-THF) δ 4.21(brs, 4H), 7.03 (s, 2H); ¹³C NMR (d₈-THF) δ 91.1, 124.5, 137.6; Anal.Calcd for C₆H₆I₂N₂: C, 20.02; H, 1.68; N, 7.78; Found: C, 20.19; H,1.59, 7.71.

Example 4

1,2-Diamino-4,5-dicyanobenzene (3). A 50 mL round-bottom flask wascharged with 2 (6.94 g, 19.3 mmol), and CuCN (6.91 g, 77.2 mmol, 4 eq),and a magnetic stirring bar. The vessel was capped with a septum andflushed with Ar for 10 min, and NMP (20 mL) was added. The vessel washeated to 120° C. for 3 h, then diluted with DMF (20 mL) and added to ahot aqueous solution of EDTA (88 g, 232 mmol, in 500 mL H₂O) in a 1 Lconical flask. Oxygen was bubbled through the mixture as it was stirredand heated for 2 h. After 2 h of this treatment, the dark heterogeneousmixture turned to a homogeneous green solution. The hot green solutionwas extracted twice with ethyl acetate, and the extracts were washedwith water, followed by brine, dried over Na₂SO₄, filtered, andconcentrated to dryness. The residue was recrystallized (EtOH/water),giving tiny tan needles (1.66 g, 55%): mp 262-264° C.; ¹H NMR(d₆-acetone) δ 5.40 (br s, 4H), 7.04 (s, 2H); ¹³C NMR (d₆-acetone) δ103.8, 117.1, 117.4, 139.4; FAB-MS obsd 158.0591, calcd 158.0592(C₆H₆N₄).

Example 5

5,6-Dicyano-2-(undec-7-yl)benzimidazole (5a). A 100 mL round-bottomflask was charged with 3 (1.32 g, 8.37 mmol), pentanol (42 mL),2-hexyl-1-octanal (1.77 g, 8.37 mmol), and a magnetic stirring bar. Theflask was fitted with a Hickman still and placed in an oil bath heatedto 120° C. NMP (4.0 mL) was added to fully dissolve the solid material.The mixture was heated and stirred for 2 h. Then FeCl₃.6H₂O (113 mg,0.42 mmol) was added to the reaction vessel and oxygen was bubbledthrough the mixture as it was heated and stirred for an additional 12 h.The reaction mixture was then removed from heat and added to 200 mLdiethyl ether. The ether solution was washed three times with water,then washed with brine, dried over Na₂SO₄, filtered, and concentrated todryness. The residue was chromatographed (silica, CHCl₃), yielding a tansolid (2.37 g, 81%): ¹H NMR ∈ 0.82 (t, J=7.6 Hz, 6H), 1.10-1.30 (m,16H), 1.77-1.87 (m, 2H), 2.90-3.04 (m, 1H), 8.07 (br s, 2H), 10.36 (brs, 1H); ¹³C NMR δ 14.2, 22.8, 27.7, 29.4, 31.8, 34.9, 41.3, 108.4,117.0, 165.3; FAB-MS obsd 351.2551, calcd 351.2549 (C₂₂H₃₀N₄).

Example 6

5,6-Dicyano-2-(4-(triisopropylsilylethynyl)phenyl)benzimidazole (5d). A25 mL round-bottom flask was charged with 3 (468 mg, 2.96 mmol), NMP (15mL), 4d (847 mg, 2.96 mmol), and a magnetic stirring bar. The flask wasfitted with a Hickman still, placed in an oil bath heated to 120° C.,and stirred for 1 h. Then FeCl₃.6H₂O (296 μL of a 100 mM solution, 30μmmol) was added to the reaction vessel and oxygen was bubbled throughthe mixture as it was heated and stirred for an additional 20 h. Thereaction mixture was then removed from heat and added to ethyl acetate.The ethyl acetate solution was washed three times with water, thenwashed with brine, dried over Na₂SO₄, filtered, and concentrated todryness. The residue was chromatographed (silica, CHCl₃, 2% ethylacetate), yielding a colorless solid (732 mg, 58%). mp 347-348° C.; ¹HNMR (d₆-acetone) δ 1.15-1.18 (m, 21H), 7.05 (d, J=8.4 Hz, 2H), 8.24-8.28(m, 4H); ¹³C NMR (d₆-acetone) δ 11.5, 18.5, 93.5, 106.7, 108.4, 116.7,118.4, 122.1 (br), 126.3, 127.6, 128.7, 132.7, 142.0 (br), 156.4; FAB-MSobsd 425.2161, calcd 425.2083 [(M+H), M=C₂₆H₂₈N₄Si].

Example 7

Synthesis of 5d directly from 2: A 2-necked 25 mL flask was charged with2 (577 mg, 1.60 mmol), CuCN (573 mg, 6.40 mmol), and NMP (2 mL). Thevessel was fitted with a bubbler and the sidearm was capped with aseptum. The mixture was heated at 120° C. for 2 h, and then more NMP (8mL) and 4d (458 mg, 1.60 mmol) were added and O₂ was bubbled through themixture. After 40 min, TLC (silica, CHCl₃, 4% isopropanol) showed thedesired product and no remaining 3 or 4d, so the mixture was transferredto a 500 mL conical flask containing a hot solution of aqueous EDTA(4.87 g, 12.8 mmol, in 200 mL) and the mixture was heated and stirredfor 30 min, and then filtered. The filter cake was dried in vacuo andchromatographed (silica, CH₂Cl₂, 2% ethyl acetate), giving a colorlesssolid (280 mg, 41%). Characterization data were identical with thepreparation from 3 above.

Example 8

5,6-Dicyano-1-propyl-2-(undec-7-yl)benzimidazole (6a). A 10 mLround-bottom flask was charged with 5a (743 mg, 2.12 mmol), and CH₃CN(2.0 mL). The flask was capped with a septum and placed in an oil bathheated to 80° C. DBU (317 μL, 2.12 mmol) was added, and the mixture wasstirred for 2 min. Then iodopropane (207 μL, 2.12 mmol) was added andthe mixture was stirred for 20 min. A second dose of DBU (317 μL, 2.12mmol), followed by iodopropane (207 μL, 2.12 mmol), was added, and 20min later, a third identical round of DBU and iodopropane was againadded. HPLC analysis of the reaction mixture (C-18 reverse phase, CH₃CNas isocratic eluent) indicated that the yields of the reaction after thefirst, second, and third round of reagents were 60%, 78%, and 97%,respectively. After the third round of reagents was added and themixture was stirred for 20 min, the reaction mixture was removed fromheat and added to 200 mL diethyl ether. The ether solution was washedthree times with water, then washed with brine, dried over Na₂SO₄,filtered, and concentrated to dryness. The residue was chromatographed(silica, hexanes/ethyl acetate 7:1, then hexanes/ethyl acetate 6:1),yielding a tan solid (786 mg, 94%): mp 52-53° C.; ¹H NMR δ 0.81 (t,J=6.8 Hz, 6H), 1.02 (t, J=7.2 Hz, 3H), 1.05-1.13 (m, 16H), 1.72-1.82 (m,6H), 2.88-2.98 (m, 1H), 4.15 (t, J=7.6 Hz, 2H); ¹³C NMR δ 11.6, 14.2,14.2, 22.8, 23.8, 27.8, 29.5, 31.8, 35.2, 38.3, 45.9, 107.8, 108.4,116.2, 116.9, 117.0, 125.8, 137.0, 145.3, 165.5; Anal. Calcd forC₂₅H₃₆N₄: C, 76.49; H, 9.24; N, 14.27; Found C, 17.38; H, 9.36; N,14.18.

Example 9

5,6-Dicyano-2-phenyl-1-propylbenzimidazole (6b). A 25 mL round-bottomflask was charged with 3 (316 mg, 2.00 mmol), NMP (10 mL), benzaldehyde,(202 μL, 2.00 mmol), and a magnetic stirring bar. The flask was fittedwith a Hickman still, placed in an oil bath heated to 120° C., andstirred for 1 h. Then FeCl₃.6H₂O (27 mg, 0.10 mmol) was added to thereaction vessel and oxygen was bubbled through the mixture as it washeated and stirred for an additional 20 h. The reaction mixture was thenremoved from heat and added to ethyl acetate. The ethyl acetate solutionwas washed three times with water, then washed with brine, dried overNa₂SO₄, filtered, and concentrated to dryness. The residue (458 mg, 1.88mmol) was dissolved in NMP (2 mL) and heated to 80° C. Then DBU (280 μL,1.88 μmol) was added and the mixture was stirred for 2 min, andiodopropane (183 μL, 1.88 mmol) was added. After 20 min, the mixture wastreated with a second round of DBU and iodopropane, and after anadditional 20 min, a third round of reagents was added. After a final 20min of heating, the mixture was transferred to ethyl acetate and washedthree times with water, followed by brine. After drying the organiclayer over Na₂SO₄, the mixture was filtered, concentrated to dryness,and chromatographed (silica, CH₂Cl₂, 3% ethyl acetate, 1% isopropanol),yielding an off-white solid (253 mg, 44%): mp 183-185° C.; ¹H NMR(CDCl₃) δ 0.90 (t, J=7.6 Hz, 2H), 1.81-1.92 (m, 2H), 4.29 (t, J=7.6 Hz,2H), 7.56-7.62 (m, 3H), 7.70-7.73 (m, 2H), 7.89 (s, 1H), 8.20 (s, 1H);¹³C NMR (CDCl₃) δ 11.4, 23.5, 47.3, 108.7, 109.0, 116.7, 116.8, 116.9,126.6, 128.8, 129.5, 129.5, 131.4, 137.8, 145.4, 159.5; FAB-MS obsd287.1302, calcd 287.1297 [(M+H)⁺; M=C₁₈H₁₄N₄].

Example 10

5,6-Dicyano-2-(4-iodophenyl)-1-propylbenzimidazole (6c). A 25 mLround-bottom flask was charged with 3 (340 mg, 2.15 mmol), NMP (10 mL),4-iodobenzaldehyde, (499 mg, 2.15 mmol), and a magnetic stirring bar.The flask was fitted with a Hickman still, placed in an oil bath heatedto 120° C., and stirred for 1 h. Then FeCl₃.6H₂O (29 mg, 0.11 mmol) wasadded to the reaction vessel and oxygen was bubbled through the mixtureas it was heated and stirred for an additional 24 h. The reactionmixture was then removed from heat and added to ethyl acetate. The ethylacetate solution was washed three times with water, then washed withbrine, dried over Na₂SO₄, filtered, and concentrated to dryness. Theresidue (603 mg, 1.63 mmol) was suspended in CH₃CN and heated to 80° C.Then DBU (243 μL, 1.63 μmol) was added and the mixture was stirred for 2min, and iodopropane (159 μL, 1.63 mmol) was added. After 20 min, themixture was treated with a second round of DBU and iodopropane, andafter an additional 20 min, a third round of reagents was added. After afinal 20 min of heating, the mixture was transferred to ethyl acetateand washed three times with water, followed by brine. After drying theorganic layer over Na₂SO₄, the mixture was filtered, concentrated todryness, and chromatographed (silica, CHCl₃, 5% ethyl acetate), giving awhite solid (440 mg, 50%): mp 208-209° C.; ¹H NMR (CDCl₃) δ 0.91 (t,J=7.6 Hz, 3H), 1.80-1.91 (m, 2H) 4.26 (t, J=7.6 Hz, 2H), 7.46 (d, J=8.0Hz, 2H), 7.87 (s, 1H), 7.95 (d, J=8.0 Hz, 2H), 8.22 (s, 1H); ¹³C NMR(CDCl₃) δ 11.4, 23.6, 47.4, 98.4, 109.0, 109.3, 116.55, 116.62, 116.9,126.7, 128.2, 130.9, 137.8, 138.7, 145.3, 158.4; Anal. Calcd forC₁₈H₁₃IN₄: C, 52.45; H, 3.18; N, 13.59; Found: C, 52.40; H, 3.06; N,13.40.

Example 11

5,6-Dicyano-2-(4-(triisopropylsilylethynyl)phenyl)-1-propylbenzimidazole(6d). A 20 mL vial was charged with 5d (763 mg, 1.79 mmol), and NMP (10mL). The vial was capped with a septum and placed in an oil bath heatedto 120° C. DBU (267 μL, 1.79 mmol) was added, and the mixture wasstirred for 2 min. Then iodopropane (175 μL, 1.79 mmol) was added andthe mixture was stirred for 20 min. A second dose of DBU (267 μL, 1.79mmol), followed by iodopropane (175 μL, 1.79 mmol), was added, and 20min later, a third identical round of DBU and iodopropane was againadded. After the third round of reagents was added and the mixture wasstirred for 20 min, the reaction mixture was removed from heat and addedto ethyl acetate. The solution was washed three times with water, thenwashed with brine, dried over Na₂SO₄, filtered, and concentrated todryness. The residue was chromatographed (silica, CHCl₃), yielding acolorless solid (506 mg, 61%): mp 242-243° C.; ¹H NMR (d₆-acetone) δ0.89 (t, J=7.2 Hz, 3H), 1.17-1.19 (m, 21H), 1.86-1.96 (m, 2H), 4.53 (t,J=7.6 Hz, 2H), 7.75 (d, J=8.0 Hz, 2H), 7.91 (d, J=8.0 Hz, 2H), 8.36 (s,1H), 8.50 (s, 1H); ¹³C NMR (d₆-acetone) δ 10.5, 11.3, 18.4, 23.2, 47.1,93.1, 106.6, 108.1, 108.3, 116.8, 116.9, 118.3, 125.8, 126.3, 129.6,129.9, 132.5, 138.5, 145.4, 158.4; Anal. Calcd for C₂₉H₃₄N₄Si: C, 74.63;H, 7.34; N, 12.01; Found: C, 74.75; H, 7.32; N, 12.01.

Example 12

Tetrakis(2-tridec-7-yl-1-propylbenzimidazo[5,6-b:5′,6′-g:5″,6″-l:5′″,6′″-q])porphyrazine(Fb-7). A 5 mL reaction vial was charged with 6a (150 mg, 382 μmol),pentanol (1.90 mL), and a magnetic stirring bar. The vial was capped andheated in a heating block set at 145° C. and then DBU (57 μL, 382 μmol)was added. Heating and stirring continued for 18 h. The vial was thenremoved from heat, and upon cooling to room temperature, the mixture wasdiluted with 18 mL of MeOH, and then centrifuged. The supernatant wasremoved and the pellet was resuspended in MeOH and centrifuged again.After removing the supernatant the second time, the pellet wasredissolved in THF (2 mL) and precipitated by addition of MeOH (18 mL).The mixture was centrifuged, and upon removal of the supernatant, thepellet was dried in vacuo, revealing a green solid (17 mg, 11%): ¹H NMR(d₈-THF) δ 0.30-0.50 (br s, 2H), 0.80-1.00 (m, 24H), 1.17-1.60 (m, 76H),1.80-2.10 (m, 8H), 2.10-2.42 (m, 16H), 3.10-3.25 (m, 2H), 3.30-3.40 (m,2H), 4.30-4.50 (m, 4H), 4.70-4.84 (m, 4H), 9.30-9.70 (m, 8H); LD-MS obsd1570.8; FAB-MS obsd 1571.2178, calcd 1571.1916 (C₁₀₀H₁₄₆N₁₆); λ_(abs)(nm) 309, 342, 376, 640, 676, 713, 737; λ_(em) 742 nm; Φ_(f)=0.59.

Example 13

Preparation of Fb-7 using Lithium pentoxide: A 5 mL reaction vial wascharged with a magnetic stirring bar, pentanol (1.0 mL), and Li ribbon(23 mg, 3.3 mmol). The vial was capped, vented and warmed to 90° C.After all of the Li was consumed (40 min) the vial was removed from heatand allowed to cool to room temperature. Then a pentanol solution of 6a(150 mg, 0.382 mmol, in 1.0 mL) was added, and the vial was capped andheated to 140° C. for 4 h. The vial was then removed from heat and, uponcooling to room temperature, the reaction mixture was diluted into 18 mLof MeOH (2% CH₃CO₂H). The mixture was centrifuged, and the supernatantwas removed. The supernatant was removed and the pellet was resuspendedin MeOH and centrifuged again. After removing the supernatant the secondtime, the pellet was redissolved in THF (2 mL) and precipitated byaddition of MeOH (18 mL). The mixture was centrifuged, and upon removalof the supernatant, the pellet was dried in vacuo, giving a green solid(74 mg, 49%). Characterization data were consistent with the materialproduced from the DBU-mediated reaction (vide supra).

Example 14

Tetrakis(2-tridec-7-yl-1-propylbenzimidazo[5,6-b:5′,6″-g:5″,6″-l:5′″,6′″-q])porphyrazinatomagnesium(II)(Mg-7). A 5 mL reaction vial was charged with 6a (150 mg, 382 μmol),MgCl₂ (13 mg, 96 μmol), pentanol (1.90 mL), and a magnetic stirring bar.The vial was capped and heated in a heating block set at 145° C. andthen DBU (57 μL, 382 μmol) was added. Heating and stirring continued for18 h. The vial was then removed from heat, and upon cooling to roomtemperature, the mixture was diluted with 16 mL of MeOH and 2 mL ofwater, and then centrifuged. The supernatant was removed and the pelletwas resuspended in MeOH/water (8:1), and centrifuged again. Afterremoving the supernatant the second time, the pellet was redissolved inTHF (2 mL) and precipitated by addition of MeOH (16 mL) and water (2mL). The mixture was centrifuged, and upon removal of the supernatant,the pellet was dried in vacuo, giving a green solid (41 mg, 27%): ¹H NMR(d₈-THF) δ 0.82-0.96 (m, 24H), 1.16-1.58 (m, 76H), 1.87-2.02 (m, 8H),2.18-2.36 (m, 16H), 3.24-3.34 (m, 4H), 4.66-4.74 (m, 8H), 9.40 (s, 2H),9.47 (s, 2H), 9.65 (s, 2H), 9.68 (s, 2H); LD-MS obsd 1592.7; FAB-MS obsd1593.1650, calcd 1593.1610 (C₁₀₀H₁₄₄MgN₁₆); λ_(abs) (nm) 310, 363, 640,680, 713; λ_(em) 720 nm; Φ_(f)=0.69.

Example 15

Tetrakis(2-tridec-7-yl-1-propylbenzimidazo[5,6-b:5′,6′-g:5″,6″-l:5′″,6′″-q])porphyrazinatozinc(II)(Zn-7). A 5 mL reaction vial was charged with 6a (150 mg, 382 μmol) anda magnetic stirring bar. The vial was then introduced into a gloveboxunder Argon atmosphere and ZnCl₂ (13 mg, 96 μmol) was added. The vialwas capped and removed from the glove box, and pentanol (1.90 mL) wasadded. The vial was heated to 140° C. in a heating block and then DBU(57 μL, 382 μmol) was added. The temperature of the heating block wasraised to 145° C. and continued for 18 h. The vial was then removed fromheat, and upon cooling to room temperature, the mixture was diluted with16 mL of MeOH and 2 mL of water, and then centrifuged. The supernatantwas removed and the pellet was resuspended in MeOH and centrifugedagain. After removing the supernatant the second time, the pellet wasredissolved in THF (2 mL) and precipitated by addition of MeOH (16 mL)and water (2 mL). The mixture was centrifuged, and upon removal of thesupernatant, the pellet was dried in vacuo, giving a green solid (72 mg,46%): ¹H NMR (d₈-THF) δ 0.82-0.95 (m, 24H), 1.20-1.60 (m, 76H),1.88-2.05 (m, 8H), 2.17-2.35 (m, 16H), 3.20-3.35 (m, 4H), 4.60-4.80 (m,8H), 9.45 (s, 2H), 9.50 (s, 2H), 9.64-9.74 (m, 4H); LD-MS obsd 1633.0;FAB-MS obsd 1633.1111, calcd 1633.1051 (C₁₀₀H₁₄₄N₁₆Zn); λ_(abs) (nm)309, 357, 640, 681, 713; λ_(em) 724 nm; Φ_(f)=0.47.

Example 16

Tetrakis(2-phenyl-1-propylbenzimidazo[5,6-b:5′,6′-g:5″,6″-l:5′″,6′″-q])porphyrazine(Fb-8). A 5 mL reaction vial was charged with 6b (50.0 mg, 0.175 μmol),pentanol (875 μL) and a magnetic stirring bar. The vial was capped andheated in a heating block set to 145° C. and then DBU (26 μL, 175 μmol)was added. Heating and stirring continued for 18 h. The vial was thenremoved from heat, and upon cooling to room temperature, the mixture wasdiluted with 18 mL of MeOH, and then centrifuged. The supernatant wasremoved and the pellet was resuspended in MeOH and centrifuged again.This suspension-centrifugation procedure was repeated a third time.After removing the supernatant the third time, the pellet wasredissolved in THF (4 mL) and precipitated by addition of MeOH (15 mL)and water (0.5 mL). The mixture was centrifuged, and upon removal of thesupernatant, the pellet was dried in vacuo, giving a green solid (19 mg,38%). The sample was found to be a regioisomeric mixture of products,which resulted in some ¹H NMR resonances having non-integerintegrations: ¹H NMR (d₈-THF) δ−3.13 (br s, 2H), 1.02-1.25 (m, 12H),2.04-2.34 (m, 8H), 4.18-4.56 (m, 8H), 7.50-7.70 (m 12H), 7.90-8.08 (m,8H), 8.12-8.22 (br s, 1H), 8.28-8.77 (m, 5H), 8.90-8.96 (m, 0.5H),9.00-9.12 (m, 1.5H); LD-MS obsd 1146.7; FAB-MS obsd 1147.5127, calcd1147.5109 [(M+H)⁺; M=C₇₂H₅₈N₁₆].

Example 17

Preparation of Fb-8 using Lithium pentoxide: A 5 mL reaction vial wascharged with a magnetic stirring bar, pentanol (875 μL), and Li ribbon(10.0 mg, 1.44 mmol). The vial was capped, vented and warmed to 90° C.After all of the Li was consumed (1 h) the vial was removed from heatand allowed to cool to room temperature. Then 6b (50 mg, 175 μmol) wasadded, and the vial was and heated in a heating block set to 145° C. for18 h. The vial was then removed from heat and, upon cooling to roomtemperature, the reaction mixture was diluted into 18 mL of MeOH (2%CH₃CO₂H). The mixture was centrifuged, and the supernatant was removed.The supernatant was removed and the pellet was resuspended in MeOH andcentrifuged again. This suspension-centrifugation procedure was repeateda third time. After removing the supernatant the third time, the pelletwas redissolved in THE (4 mL) and precipitated by addition of MeOH (15mL) and water (0.5 mL). The mixture was centrifuged again, and uponremoval of the supernatant, the pellet was dried in vacuo, giving agreen solid (14 mg, 28%). Characterization data were consistent with thematerial produced from the DBU-mediated reaction (vide supra).

Example 18

Tetrakis(2-phenyl-1-propylbenzimidazo[5,6-b:5′,6′-g:5″,6″-l:5′″,6′″-q])porphyrazinatomagnesium(II)(Mg-8). A 5 mL reaction vial was charged with 6b (50.0 mg, 0.175 μmol),MgCl₂ (4.2 mg, 44 μmol), pentanol (875 μL) and a magnetic stirring bar.The vial was capped and heated in a heating block set to 145° C. andthen DBU (26 μL, 175 μol) was added. Heating and stirring continued for18 h. The vial was then removed from heat, and upon cooling to roomtemperature, the mixture was diluted with 18 mL of MeOH, and thencentrifuged. The supernatant was removed and the pellet was resuspendedin MeOH and centrifuged again. This suspension-centrifugation procedurewas repeated a third time. After removing the supernatant the thirdtime, the pellet was redissolved in THF (4 mL) and precipitated byaddition of MeOH (15 mL) and water (0.5 mL). The mixture wascentrifuged, and upon removal of the supernatant, the pellet was driedin vacuo, giving a green solid (33 mg, 65%): ¹H NMR (d₈-THF) δ 1.12-1.22(m, 12H), 2.22-2.34 (m, 8H), 4.83-4.92 (m, 8H), 7.59-7.72 (m, 12H),8.06-8.12 (m, 8H), 9.55 (br s, 2H), 9.63 (br s, 2H), 9.76-9.84 (m, 4H);LD-MS obsd, 1168.8; FAB-MS obsd 1168.4695, calcd 1168.4724(C₇₂H₅₆MgN₁₆); λ_(abs) (nm) 314, 364, 643, 684, 717; λ_(em) 724 nm;Φ_(f)=0.84.

Example 19

Tetrakis(2-phenyl-1-propylbenzimidazo[5,6-b:5′,6′-g:5″,6″-l:5′″,6′″-q])porphyrazinatozinc(II)(Zn-8). A 5 mL reaction vial was charged with 6b (50.0 mg, 0.175 μmol),and a magnetic stirring bar. The vial was then introduced into aglovebox under an argon atmosphere and ZnCl₂ (6.0 mg, 44 μmol) wasadded. The vial was capped and removed from the glove box, and pentanol(875 μL) was added. The vial was capped and heated in a heating blockset to 145° C. and then DBU (26 μL, 175 μmol) was added. Heating andstirring continued for 18 h. The vial was then removed from heat, andupon cooling to room temperature, the mixture was diluted with 18 mL ofMeOH, and then centrifuged. The supernatant was removed and the pelletwas resuspended in MeOH and centrifuged again. Thissuspension-centrifugation procedure was repeated a third time. Afterremoving the supernatant the third time, the pellet was redissolved inTHF (4 mL) and precipitated by addition of MeOH (15 mL) and water (0.5mL). The mixture was centrifuged, and upon removal of the supernatant,the pellet was dried in vacuo, giving a green solid (33 mg, 62%). Thesample was found to be a regioisomeric mixture of products, whichresulted in some ¹H NMR resonances having non-integer integrations: ¹HNMR (dg-THF) δ 1.11-1.21 (m, 12H), 2.20-2.33 (m, 8H), 4.72-4.86 (m, 8H),7.60-7.71 (m, 12H), 8.05-8.12 (m, 8H), 9.30-9.43 (m, 4H), 9.49 (s,0.5H), 9.59, (br s, 1.5H), 9.66 (s, 0.5H), 9.71-9.74 (m, 1.5H); LD-MSobsd, 1208.6; FAB-MS obsd 1208.4205, calcd 1208.4165 (C₇₂H₅₆N₁₆Zn);λ_(abs) (nm)); 315, 357, 643, 685, 717; λ_(em) 724 nm; Φ_(f)=0.43.

Example 20

Preparative-scale macrocyclization reaction using 6d and1,2-dicyanobenzene: A 2-necked 25 mL round-bottom flask was charged with6d (317 mg, 0.679 mmol), dicyanobenzene (130 mg, 1.02 mmol, 1.5 equiv),and a magnetic stirring bar. The flask was fitted with a condenser and abubbler, and a septum for the second neck. The apparatus was flushed for20 min with a stream of argon, and then briefly opened to add ZnCl₂ (58mg, 0.43 mmol). Then pentanol (8.5 mL) and the mixture was graduallyheated to reflux. When the mixture was homogeneous, DBU (254 μL, 1.70mmol) was added. Heating and stirring at reflux temperature wascontinued overnight (12 h). The mixture was then cooled to roomtemperature, and diluted into MeOH (300 mL) and water (50 mL). Theresulting precipitate was filtered, rinsed with EtOH, and dried invacuo. The residue was then dissolved in THF and eluted through a shortplug of silica gel in THF, and chromatographed over a column ofBio-Beads SX-3 in THF. The mixture separated into three bands. The firstband (green) appeared (by HPLC-SEC analysis) to contain compoundscontaining two and more-than-two benzimidazoles. The second band (blue)contained Zn-11. The third band (blue) contained Zn-10. The fractionscontaining Zn-10 and Zn-11 were set aside, and the first band of greenmaterial was reconcentrated and chromatographed over a column ofBio-Beads SX-1. The mixture separated into two broad green bands. Thefirst band, containing pigments having three and four benzimidazoles,could not be further purified by any chromatographic method, and wastherefore discarded. The second green band contained a mixture of Zn-12and Zn-13. The mixture was separated by chromatography (silica, CHCl₃,2% isopropanol).

Example 21

Zinc Phthalocyanine (Zn-10, A₄). The compound was isolated as a blueband from chromatography on Bio-Beads SX-3 (vide supra). The THFsolution was concentrated and the residue was chromatographed over ashort column (silica, CHCl₃, 2% isopropanol). Fractions containing theproduct were concentrated, giving a blue solid (10 mg, 4%): ¹H NMR(d₈-THF) δ 8.17-8.23 (m, 8H), 9.45-9.50 (m, 8H); LD-MS obsd, 576.3;FABMS obsd 576.0813, calcd 576.0789 (C₃₂H₁₆N₈Zn); λ_(abs) 666 nm.

Example 22

Tribenzo[g,l,q]-(2-{4-(2-triisopropylsilylethynyl)phenyl}-1-propylbenzimidazo[5,6-b])porphyrazinatozinc(H)(Zn-11, A₃B). The compound was isolated as a blue band fromchromatography on Bio-Beads SX-3 (vide supra). The THF solution wasconcentrated and the residue was chromatographed over a short column(silica, CHCl₃, 2% isopropanol). Fractions containing the product wereconcentrated, giving a blue solid (86 mg, 22%): ¹H NMR (d₈-THF) δ 1.14(t, J=7.2 Hz, 3H), 1.27 (s, 21H), 2.16-2.26 (m, 2H), 4.75 (t, J=7.6 Hz,2H), 7.82 (d, J=8.0 Hz, 2H), 8.00-8.15 (m, 8H), 9.09 (s, 1H), 9.13 (d,J=7.6 Hz, 1H), 9.22-9.34 (m, 5H), 9.37 (s, 1H); LD-MS obsd, 914.7;FAB-MS obsd 914.2986, calcd 914.2968 (C₅₃H₄₆N₁₀SiZn); λ_(abs) (nm): 340,611, 674; λ_(em) 692 nm; Φ_(f)=0.47.

Example 23

Dibenzo[l,q]-(2-{4-(2-triisopropylsilylethyl)phenyl}-1-propylbenzimidazo[5,6-b:5′,6′-g])porphyrazinatozinc(II)(Zn-12, cis-A₂B₂). The compound was isolated from silica gelchromatography (vide supra) as the first green band and concentrated togive a green solid (74 mg, 14%): ¹H NMR (d₈-THF) δ 1.09-1.20 (m, 6H),2.15-2.30 (m, 4H), 4.81 (t, J=7.6 Hz, 4H), 7.76-7.84 (m, 4H), 8.06-8.19(m, 8H), 9.12-9.50 (m, 5H), 9.63 (s, 1H), 9.70 (s, 1H); LD-MS obsd1252.5; FAB-MS obsd 1252.5148, calcd 1252.5146 (C₇₄H₇₆N₁₂Si₂Zn); λ_(abs)(nm): 340, 623, 693; λ_(em) 701 nm; Φ_(f)=0.44.

Example 24

Dibenzo[g,q]-(2-{4-(2-triisopropylsilylethynyl)phenyl}-1-propylbenzimidazo[5,6-b:5′,6′-l])porphyrazinatozine(II)-C_(2v)(Zn-13b, trans-A₂B₂). The compound was isolated from chromatography asthe second green band and concentrated to give a green solid (4 mg, 1%).Characterization data were consistent with the compound Zn-13b isolatedfrom the metallation of Fb-13 (vide infra): ¹H NMR (d₈-THF) δ 1.15 (t,J=7.2 Hz, 6H), 1.25 (s, 42H), 2.20-2.28 (m, 4H), 4.81 (t, J=7.2 Hz, 4H),7.79 (d, J=8.4 Hz, 4H), 8.09 (d, J=8.4 Hz, 4H), 8.12-8.17 (m, 2H),8.17-8.22 (m, 2H), 9.37 (s, 2H), 9.37-9.42 (m, 2H), 9.43-9.48 (m, 2H),9.60 (s, 2H); LD-MS obsd 1252.6, calcd 1252.5 (C₇₄H₇₆N₁₂Si₂Zn); λ_(abs)(nm): 335, 679, 708; FAB-MS and fluorescence data were not separatelyobtained for this sample, but were obtained for the sample reported fromthe metallation of Fb-13.

Example 25

Tribenzo[g,l,q]-(2-{4-(2-triisopropylsilylethynyl)phenyl}-1-propylbenzimidazo[5,6-b])porphyrazine(Fb-11, A₃B). A 20 mL reaction vial was charged with 14a (40.0 mg, 83μmol), boron subphthalocyanine 15 (143 mg, 332 μmol, 4 equiv), DMAE (4mL), and a magnetic stirring bar. The vial was capped and heated in anoil bath maintained at 100° C. Periodically, a few microliters of thereaction mixture were removed, diluted into Tiff, and analyzed by UV-Visspectroscopy. After the reaction had proceeded for 10 h, 15 could not beobserved in the UV-Vis spectrum. The reaction was then cooled to roomtemperature and diluted with MeOH (50 mL) and water (30 mL). The mixturewas filtered through paper, and the solid residue was rinsed with MeOHand air-dried. The filter paper containing the solid residue was thenloaded into a Soxhlet thimble and the thimble was extracted with CHCl₃for 20 h. Upon cooling the apparatus, most of the extracted pigmentprecipitated out of the filtrate. The solvent was removed from thefiltrate under reduced pressure and the solid material was resuspendedin THF (20 mL) with sonication. The mixture was filtered through acotton-plugged pipette and chromatographed over a column of Bio-BeadsSX-3 in THF. The desired compound was recovered from the column as adark blue-green band that eluted just after a faint green band andbefore a purple band. The faint green band was identified by UV-Vis as amixture of benzimidazoporphyrazines having more than one benzimidazole,and was discarded. The purple band was identified by UV-Vis as a mixtureof trace remaining subPc 15 and unsubstituted phthalocyanine and wasdiscarded. The fractions containing the desired compound wereconcentrated and chromatographed over silica gel (CH₂Cl₂, 2%isopropanol, 2.5% THF, 2.5% ethyl acetate). Fractions containing thedesired compound were concentrated, giving a blue solid (18 mg, 25%): ¹HNMR δ −3.29 (br s, 2H), 1.17 (t, J=7.6 Hz, 3H), 1.32 (s, 21H), 2.10-2.25(m, 2H), 4.45-4.60 (m, 2H), 7.68 (t, J=7.2 Hz, 1H), 7.75-7.94 (m, 4H),7.87 (d, J=8.0 Hz, 4H), 8.11 (d, J=8.0 Hz, 4H), 8.24-8.32 (m, 1H),8.52-8.66 (m, 3H), 8.68-8.82 (m, 4H); LD-MS obsd 852.5; FAB-MS obsd853.3945, calcd 853.3911 [(M+H)⁺; M=C₅₃H₄₈N₁₀Si] λ_(abs) (nm) 337, 622,649, 669, 695; λ_(em) (nm) 700, 714; Φ_(f)=0.68.

Example 26

Dibenzo[g,q]-(2-{4-(2-triisopropylsilylethynyl)phenyl}-1-propylbenzimidazo[5,6-b:5′,6′-l])porphyrazine(Fb-13, trans-A₂B₂). An oven-dried three-necked 300 mL round bottomflask was charged with 14 (465 mg, 0.96 mmol), and a magnetic stirringbar. The vessel was flushed with argon for 10 min and immersed in an icebath. Freshly dried THF (70 mL) and freshly dried TEA (269 μL, 1.92mmol, 2 equiv.) were added to the flask. A sample of 17 (212 mg, 0.96mmol) was dissolved in dry THF (10 mL) and slowly added to the reactionvessel. The mixture was kept at 0-5° C. for 1 h, and then allowed towarm to room temperature overnight. Then the triethylammonium salt thathad fowled was removed by filtration of the mixture into an oven-driedtwo-necked 250 mL round bottom flask. The vessel was flushed with argonfor 5 min and a solution of hydroquinone (106 mg, 0.96 mmol) in THF (10mL) was added, followed by NaOMe (658 μL of a 25 wt % solution in MeOH,2.88 mmol, 3 equiv). The mixture was refluxed for 6 h, then cooled toroom temperature and poured into MeOH (20 mL), to which water (100 mL)was added. After standing for 1 h, the mixture was filtered and thesolid residue was air dried, dissolved in CH₂Cl₂, and chromatographed(silica, CH₂Cl₂, 1% isopropanol, 5% ethyl acetate, 5% THF). The firstgreen band (faint) was identified by LD-MS as the AB₃ macrocycle (LD-MSm/z 1526.0). The product was collected as the second (dark) green band(49 mg, 9%): ¹H NMR δ −4.32 (br s, 1H), −4.22 (br s, 1H), 1.02 (t, J=6.8Hz, 3H), 1.10 (t, J=6.8 Hz, 3H), 1.34 (s, 42H), 1.82-2.10 (m, 4H),4.10-4.38 (m, 4H), 7.29-7.37 (m, 1H), 7.47-7.64 (m, 4H), 7.74-7.83 (m,4H), 7.83-7.90 (m, 1H), 7.91 (d, J=7.6 Hz, 2H), 7.95 (d, J=8.4 Hz, 2H),7.99-8.15 (m, 4H), 8.17-8.24 (m, 1H), 8.29-8.47 (m, 1H); LDMS obsd1190.7; FABMS obsd 1190.6040, calcd 1190.6011 (C₇₄H₇₈N₁₂Si₂); λ_(abs)(nm): 340, 610, 631, 662, 681, 703, 732; λ_(em) (nm): 711, 739;Φ_(f)=0.66.

Example 27

Dibenzo[g,q]-(2-{4-(2-triisopropylsilylethynyl)phenyl}-1-propylbenzimidazo[5,6-b:5′,6′-l])porphyrazinatozine(n)(Zn-13, trans-A₂B₂). From cross-condensation reaction: An oven-dried 20mL reaction vial was charged with 14 (48 mg, 99 μmol), and a magneticstirring bar. The vial was capped with a septum flushed with argon for10 min and immersed in an ice bath. Freshly dried THF (8 mL) and freshlydried TEA (28 μL, 0.20 mmol, 2 equiv.) were added to the vial. A sampleof 16 (22 mg, 99 μmol) was dissolved in dry THF (2 mL) and slowly addedto the reaction vial. The mixture was kept at 0-5° C. for 1 h, and thenallowed to warm to room temperature overnight. Then the triethylammoniumsalt that had formed was removed by filtration of the mixture into anoven-dried 25 mL round bottom flask. Hydroquinone (11 mg) was added andthe vessel was flushed with argon for 5 min and NaOMe (69 μL of a 25 wt% solution in MeOH, 0.30 mmol, 3 equiv) was added. The mixture wasrefluxed for 6 h, then cooled to room temperature and poured into MeOH(50 mL), to which water (2 mL) was added. After standing for 1 h, themixture was filtered and the solid residue was air dried, dissolved inCH₂Cl₂, and chromatographed (silica, CH₂Cl₂, 1% isopropanol, 2.5% ethylacetate, 2.5% THF). The first green band (faint) was identified by LD-MSas the ZnAB₃ macrocycle (LD-MS m/e 1591.0). The product was collected asthe second (dark) green band (5.0 mg, 4%): ¹H NMR δ 1.15 (t, J=7.6 Hz,6H), 1.28 (s, 42H), 2.13-2.25 (m, 4H), 4.69 (t, J=7.6 Hz, 4H), 7.80 (d,J=8.0 Hz, 4H), 8.02-8.20 (m, 4H), 8.09 (d, J=8.0 Hz, 4H), 9.06-9.13 (m,1H), 9.18-9.24 (m, 2H), 9.29-9.43 (m, 5H); LD-MS obsd 1252.5; FAB-MSobsd 1252.5242, calcd 1252.5146 (C₇₄H₇₆N₁₂Si₂Zn); λ_(abs) (nm): 338,614, 648, 679, 709. Fluorescence data were not collected from thissample, but were collected for the separate regioisomers (vide infra).

From zinc-metalation of Fb-13: A 20 mL reaction vial was, charged withFb-13 (20 mg, 17 μmol), Zn(OAc)₂.2H₂O (7.4 mg, 34 μmol, 2 equiv),dioxane (2.0 mL), DMF (0.5 mL), and a magnetic stirring bar. The vialwas kept in an oil bath heated to 100° C. for 2 h, upon which the UV-Visabsorbance analysis of a removed sample showed a spectrum for Zn-13 withno evidence of remaining starting material. The reaction mixture wascooled and diluted to 20 mL with MeOH. The mixture was filtered and thesolid was air dried, then dissolved through the filter with THF, andconcentrated to dryness. The residue was chromatographed (silica,toluene, 10% THF) to separate a trace of remaining Fb-13 that was toosmall to be detected in the mixture by UV-Vis analysis. The producteluted as the first (dark) green band (19 mg, 90%). A secondchromatography (silica, CH₂Cl₂, 1% isopropanol, 5% ethyl acetate, 5%THF) separated the two regioisomeric products. The first green band wasassigned as Zn-13a. Fractions containing the second green band wererechromatographed twice to separate all trace of the first elutingisomer. The second eluting species was assigned as Zn-13b. These twoisomers, Zn-13a and Zn-13b, were determined by their COSY NMR data to bethe C_(2h) and C₂, symmetric structures, respectively.

Data for Zn-13a (C_(2h)): yield=10.0 mg (47%); ¹H NMR δ 1.16 (t, J=8.0Hz, 6H), 1.28 (s, 42H), 2.14-2.26 (m, 4H), 4.71 (t, J=8.0 Hz, 4H), 7.81(d, J=8.0 Hz, 4H), 8.02-8.14 (m, 4H), 8.08 (d, J=8.0 Hz, 4H), 8.88 (s,2H), 9.13 (d, J=7.2 Hz, 2H), 9.22 (s, 2H), 9.23 (d, J=7.2 Hz, 2H); LD-MSobsd 1252.5; FAB-MS obsd 1252.5214, calcd 1252.5146 (C₇₄H₇₆N₁₂Si₂Zn);λ_(abs) (nm): 338, 614, 648, 679, 709; λ_(em) 717 nm; Φ_(f)=0.32

Data for Zn-13b (C_(2v)): yield=9.0 mg (43%); ¹H NMR δ 1.15 (t, J=7.6Hz, 6H), 1.28 (s, 42H), 2.13-2.25 (m, 4H), 4.69 (t, J=7.6 Hz, 4H), 7.79(d, J=7.6 Hz, 4H), 8.13 (d, J=7.6 Hz, 6H), 8.10-8.19 (m, 2H), 8.95 (s,2H), 9.09-9.20 (m, 2H), 9.21-9.35 (m, 4H); LD-MS obsd 1252.6; FAB-MS1252.5172, calcd 1252.5146 (C₇₄H₇₆N₁₂Si₂Zn); λ_(abs) (nm): 338, 614,648, 679, 709; λ_(em) 717 nm; Φ_(f)=0.26.

Example 28

2-(4-(2-(Triisopropylsilyl)ethynyl)phenyl)-1-propylimidazo[4,5-f]isoindole-1,3-diimine(14). A 25 mL round bottom flask was charged with 6d (606 mg, 1.30 mmol)and a magnetic stirring bar. The vessel was sealed with a condenser, abubbler, and a septum for the second neck. The apparatus was flushedwith argon for 15 min, and then anhydrous MeOH (14 mL), freshly driedTHF (7 mL), and NaOMe (30 μL of a 25 wt % solution in MeOH, 130 μmol)were added. The reaction flask was heated in an oil bath at 70° C., andthe mixture became homogeneous. The argon line was removed and ammoniagas was bubbled through the mixture as it refluxed for 6 h. The flaskwas then removed from heat and allowed to cool under ammonia atmosphere.When the mixture reached room temperature, the ammonia gas flow wasstopped and the mixture was allowed to stand overnight under a slowlyflowing stream of argon, during which time some greenish-white crystalsformed in the vessel. The supernatant was drained off with a pipette andthe crystals were washed with a few milliliters of anhydrous MeOH, andthen dried in vacuo. Yield: 479 mg, 76%: mp 248-250° C., upon which thesample melted and turned deep green—the melting capillary was broken andthe residue taken up in THF and analyzed by UV-Vis spectroscopy, whichshowed a spectrum similar to that of Fb-8; Due to the presence oftautomeric forms of the product, the NH signals do not all integrate tointegers: ¹H NMR (d₈-THF) δ 0.86 (t, J=7.2 Hz, 3H), 1.19 (s, 21H),1.80-1.92 (m, 2H), 3.14 (br s, 0.5H), 4.30-4.44 (m, 2H), 7.48 (br s,0.5H), 7.65 (d, J=8.0 Hz, 2H), 7.83 (d, J=8.0 Hz, 2H), 7.80-8.60 (m,4H); Due to poor solubility, ¹³C NMR spectroscopy was not performed; IR(film): 3260, 3201, 2941, 2861, 2161, 1666, 1547, 1460, 1410, 1345,1144, 1109, 1081, 1054, 994, 916, 882; Anal. Calcd for C₂₉H₃₇N₅Si: C,72.01; H, 7.71; N, 14.48; Found: C, 69.90; H, 7.86; N, 13.91 (consistentwith crystal inclusion of one molecule MeOH per molecule compound;FAB-MS obsd 484.2876, calcd 484.2896 [(M+H)⁺; M=C₂₉H₃₇N₅Si].

Example 29

Dibenzo[g,q]-(2-{4-ethynylphenyl}-1-propylbenzimidazo[5,6-b:5′,6′-l])porphyrazinatozinc(II)-C_(2h)(Zn-17a, trans-A₂B₂). A 20 mL vial was charged with Zn-13a (9.5 mg, 7.6μmol), CH₂Cl₂ (4 mL), and a magnetic stirring bar. Then TBAF (17 μL of a1 M solution in THF, 17 μmol) was added, and the mixture was stirred atroom temperature for 1.5 h. TLC analysis (silica, CH₂Cl₂, 1%isopropanol, 5% ethyl acetate, 5% THF) indicated that neither startingmaterial nor intermediate remained, so the mixture was directly added toa short (15 cm) silica gel column packed in CH₂Cl₂. The product provedto be very polar, and the eluent (CH₂Cl₂, 1% isopropanol, 5% ethylacetate, 5% THF) was changed to increasing amounts of THF (final eluent:CH₂Cl₂/THF, 1:4) to elute the product as a dark blue-green band (6.2 mg,87%): ¹H NMR (d₈-THF) δ 1.17 (t, J=7.2 Hz, 6H), 2.18-2.28 (m, 4H), 3.84(s, 2H), 4.74 (t, J=8.0 Hz, 4H), 7.70 (d, J=8.4 Hz, 4H), 8.02-8.12 (m,4H), 8.05 (d, J=8.4 Hz, 2H), 9.04 (br s, 2H), 9.21 (d, J=6.4 Hz, 2H),9.26-9.32 (m, 4H); LD-MS obsd 940.8; FAB-MS obsd 940.2510, calcd940.2477 (C₅₆H₃₆N₁₂Zn).

Example 30

Dibenzo[g,q]-(2-{4-ethynylphenyl}-1-propylbenzimidazo[5,6-b:5′,6′-l])porphyrazinatozine(ID-C_(2v)(Zn-17b, trans-A₂B₂). The same procedure was followed as for Zn-17a,with the following quantities: Zn-13b (8.2 mg, 6.5 μmmol), CH₂Cl₂ (4mL), and TBAF (14 μL of a 1 M solution in THF, 14 μmol). Thechromatography procedure was followed similarly (final eluent: CH₂Cl₂,30% THF), and the product eluted as a dark blue-green band (4.4 mg,72%): ¹H NMR (d₈-THF) δ 1.15 (t, J=6.8 Hz, 6H), 2.16-2.27 (m, 4H), 3.85(s, 2H), 4.72 (t, J=7.6 Hz, 4H), 7.77 (d, J=7.6 Hz, 4H), 8.04 (d, J=7.6Hz, 6H), 8.12-8.17 (m, 2H), 9.04 (s, 2H), 9.16-9.22 (m, 2H), 9.29-9.35(m, 4H); LD-MS obsd 940.9; FAB-MS obsd 940.2490, calcd 940.2477(C₅₆H₃₆N₁₂Zn).

EXAMPLES 31-38 A Triple Decker Sandwich Complex Centered on a TripodalLinker for High Density Coverage Upon Attachment to a Surface

Three types of heteroleptic triple deckers composed of porphyrins andphthalocyanines are shown in FIG. 5. Type-c [(Pc)Ln(Pc)Ln(Por)], type-b[(Pc)Ln(Por)Ln(Pc)] and type-a [(Por)Ln(Pc)Ln(Por)] triple deckersdiffer in the number and layered arrangement of the respective porphyrinand phthalocyanine ligands. The term (Por) or (Pc) refers to the dianionof a generic porphyrin or phthalocyanine entity, respectively, in asandwich architecture without regard to the nature of the substituents.Rational routes exist for the synthesis of type-a and type-c tripledeckers (Chabach, D.; De Cian, A.; Fischer, J.; Weiss, R.; El MalouliBibout, M. Angew. Chem. Int. Ed. Engl. 1996, 35, 898-899), whereastype-b triple deckers are only available by statistical reactions(Weiss, R.; Fischer, J. In The Porphyrin Handbook; Kadish, K. M., Smith,K. M., Guilard, R., Eds.; Academic Press: San Diego, Calif., 2003; Vol.16, pp 171-246; Li, J.; Gryko, D.; Dabke, R. B.; Diers, J. R; Bocian, D.F.; Kuhr, W. G.; Lindsey, J. S. J. Org. Chem. 2000, 65, 7379-7390).

Given the greater sophistication of synthetic control in porphyrinversus phthalocyanine chemistry we have almost exclusively employedtype-c triple deckers in studies of molecular information storage(Lindsey, J. S. In The Porphyrin Handbook; Kadish, K. M., Smith, K. M.,Guilard, R., Eds.; Academic Press: San Diego, Calif., 2000; Vol. 1, pp45-118). Indeed, 14 type-c triple deckers bearing tethers attached tothe porphyrin ligand have been prepared. The generic design is shown inFIG. 6. Dyads and oligomers also have been prepared bearing one or twosurface attachment groups (Li, J.; Gryko, D.; Dabke, R. B.; Diers, J.R.; Bocian, D. F.; Kuhr, W. G.; Lindsey, J. S. J. Org. Chem. 2000, 65,7379-7390; Schweikart, K.-H.; Malinovskii, V. L.; Diers, J. R.; Yasseri,A. A.; Bocian, D. F.; Kuhr, W. G.; Lindsey, J. S. J. Mater. Chem. 2002,12, 808-828; Schweikart, K.-H.; Malinovskii, V. L.; Yasseri, A. A.; Li,J.; Lysenko, A. B.; Bocian, D. F.; Lindsey, J. S. Inorg. Chem. 2003, 42,7431-7446). For the monomeric complexes illustrated in FIG. 6, thesurface attachment groups have included aryl-SAc, benzyl-SAc,thiocyanate, benzyl alcohol, and tripodal benzyl-SAc (Gryko, D.; Li, J.;Diers, J. R.; Roth, K. M.; Bocian, D. F.; Kuhr, W. G.; Lindsey, J. S. J.Mater. Chem. 2001, 11, 1162-1180; Balakumar, A.; Lysenko, A. B.; Carcel,C.; Malinovskii, V. L.; Gryko, D. T.; Schweikart, K.-H.; Loewe, R. S.;Yasseri, A. A.; Liu, Z.; Bocian, D. F.; Lindsey, J. S. J. Org. Chem.2004, 69, 1435-1443; Wei, L.; Padmaja, K.; Youngblood, W. J.; Lysenko,A. B.; Lindsey, J. S.; Bocian, D. F. J. Org. Chem. 2004, 69, 1461-1469).The alcohol groups enable attachment to Si, whereas the thioacetategroups (which undergo deprotection in situ) enable attachment to Au orSi.

The triple decker monomers exhibited a rather low surface coverage(2.5×10⁻¹¹ mol·cm⁻²), corresponding to a large molecular footprint (˜670Å²) (Wei, L.; Padmaja, K.; Youngblood, W. J.; Lysenko, A. B.; Lindsey,J. S.; Bocian, D. F. J. Org. Chem. 2004, 69, 1461-1469). Such a largearea diminishes the surface charge density from the theoretical maximum.Achieving high surface charge density is a key objective of themolecular information storage approach. Because the tether is attachedto the porphyrin, the triple decker in principle could rotate like acamshaft, sweeping out a large area (FIG. 7). In addition, the tripledecker can tilt significantly on the surface. We felt that both thetilting and camshaft motions are the source of the substantial increasein molecular footprint and thereby diminished surface charge density.

In an effort to enforce an upright orientation of the triple decker, weprepared two triple deckers wherein each bears a tripodal tether (Wei,L.; Padmaja, K.; Youngblood, W. J.; Lysenko, A. B.; Lindsey, J. S.;Bocian, D. F. J. Org. Chem. 2004, 69, 1461-1469). The two triple deckersexhibited surface coverages of ˜1×10⁻¹¹ mol·cm⁻², which are still lessdense than possible upon close packing. A chief problem remained thatthe type-c triple decker could sweep out a large surface area byrotation about the tether axis.

We also prepared a phthalocyanine bearing the same tri-thiol tether. Thephthalocyanine was substituted at one of the β-positions via an ethynylunit. In this architecture, the cant angle of the phthalocyanine causesthe macrocycle to sweep out a larger area than would be desirable. Toeliminate the cant angle, a phthalocyanine architecture is needed thathas peripheral substituents that are aligned with one of the N-N axes ofthe macrocycle (bisecting two opposite benzo rings and two innernitrogen atoms). Phthalocyanines having such a diametrically alignedsubstitution geometry would facilitate information storage studies byenabling higher packing density in the monolayers.

We report herein the synthesis of a phthalocyanine containing oneannulated imidazo group and three unsubstituted benzo units (i.e., abenzimidazoporphyrazine), and conversion of the phthalocyanine to atype-a triple decker, where the phthalocyanine (1) is sandwiched by twotetra-p-tolylporphyrin molecules and two cerium atoms, and (2) bears acompact all-carbon (“triallyl”) tether. The triple decker lanthanidesandwich complex is centrally positioned on the tripod. The all-carbontether has been employed with metalloporphyrins, affording high surfacecoverage upon attachment to Si(100) (Padmaja, K.; Wei, L.; Lindsey, J.S.; Bocian, D. F. J. Org. Chem. 2005, 70, submitted). This approachprovides straightforward access to triple-decker architectures for highdensity surface coverage upon attachment to an electroactive surface.

Molecular Design and Synthesis Strategy. Lanthanide triple deckersandwich coordination compounds generally afford four cationic oxidationstates (Buehler, J. W.; Ng, D. K. P. In The Porphyrin Handbook; Kadish,K. M., Smith, K. M., Guilard, R., Eds.; Academic Press: San Diego,Calif., 2000; Vol. 3, pp 245-294) Cerium was chosen as the lanthanidemetal in both layers of the triple decker because each cerium undergoesa further oxidation (Ce³⁺/Ce⁴⁺), affording a total of six cationicoxidation states (Duchowski, J. K.; Bocian, D. F. J. Am. Chem. Soc.1990, 112, 8807-8811). The availability of six oxidation states isattractive for multibit storage in a given memory cell. Although we haveprepared such homonuclear cerium-containing triple deckers (Gross, T.;Chevalier, F.; Lindsey, J. S. Inorg. Chem. 2001, 40, 4762-4774), all ofthe tethered triple deckers prepared to date have contained europium oreuropium/cerium. The synthesis of the type-a triple decker is achievedby reaction of a dilithio-phthalocyanine and a porphyrin (Gross, supra).The synthesis of the imidazophthalocyanine bearing the tether at the2-imidazo position and no substituents at the other benzo rings is bestachieved by a ring-expansion reaction of a sub-phthalocyanine and thebenzimidazo-diiminoisoindoline (Kobayashi, N.; Kondo, R.; Nakajima, S.;Osa, T. J. Am. Chem. Soc. 1990, 112, 9640-9641; Musluoglu, E.; Gürek,A.; Ahsen, V.; Bekaroglu, Ö. Chem. Ber. 1992, 125, 2337-2339; Sastre,A.; Torres, T.; Hanack, M. Tetrahedron Lett. 1995, 36, 8501-8504;Weitemeyer, A.; Kliesch, H.; Wörhle; D. J. Org. Chem. 1995, 60,4900-4904; Kudrevich, S. V.; Gilbert, S.; van Lier, J. E. J. Org. Chem.1996, 61, 5706-5707). We sought to construct the phthalocyanine bearinga compact all-carbon tether via a p-phenylene unit to the 2-position ofthe imidazo unit. This design required introduction of the tether at theearliest stage in the route to the diiminoisoindoline.

Synthesis. We recently developed a new synthesis ofdicyanophenylenediamine 1 (Scheme 9), which upon reaction with a varietyof aldehydes afforded the corresponding dicyanobenzimidazoles (seeabove) A p-substituted benzaldehyde bearing the all-carbon tether (2),obtained from the commercially available p-trifluoromethylaniline, wasused in the synthesis of tripodal-tethered metalloporphyrins. Thereaction of 1 and 2 proceeded via oxidative cyclization to formbenzimidazole 3 in 57% yield, a yield consistent with our previousresults for 2-aryl-dicyanobenzimidazoles. The alkylation of 3 with1-iodopropane proceeded cleanly but incompletely, affording 4 in 62%yield accompanied by unreacted starting material (31% yield). Theaminative cyclization of 4 was performed according to a previouslypublished report (Brach, P. J.; Grammatica, S. J.; Ossanna, O. A.;Weinberger, L. J. Heterocyclic Chem. 1970, 7, 1403-1405), affordingdiiminoisoindoline 5 in 48% yield. Although this procedure typicallyaffords yields >90%, the lower yield of 5 is attributed to incompleterecovery from the cooled methanolic reaction mixture.

The ring expansion reaction of subphthalocyanines such as 6 (Claessens,C. G.; Gonzalez-Rodriguez, D.; del Rey, B.; Torres, T.; Mark, G.;Schuchmann, H. P.; von Sonntag, C.; MacDonald, J. G.; Nohr, R. S. Eur.J. Org. Chem. 2003, 14, 2547-2551) has been reported under variousprocedures. We chose a procedure using the polar, reducing solvent2-dimethylaminoethanol (DMAE) (Sastre, A.; Torres, T.; Hanack, M.Tetrahedron Lett. 1995, 36, 8501-8504). Due to the good reactivity of 5,four equivalents of 6 were required to suppress the formation ofproducts bearing more than one imidazo moiety. After 8 h of reaction,the presence of reactant 6 was no longer evident and a substantialamount of unsubstituted phthalocyanine was formed in addition to thedesired imidazophthalocyanine H₂-7. The macrocycles were separated fromthe DMAE by precipitation with MeOH. H₂-7 is sufficiently more solublethan the unsubstituted phthalocyanine to be largely separated by Soxhletextraction using CH₂Cl₂. Complete purification required size exclusionchromatography and adsorption chromatography.

The lithiation of H₂-7 (Scheme 10) was carried out so as to avoid anytrace of unreacted Li metal, owing to concern for the sensitivity of theallyl groups. The reaction was followed by UV-Vis spectroscopy, and theformation of Li₂-7 was evident within 15 min. The product Li₂-7 hasgreatly improved solubility compared to the free base H₂-7, similar tothe previous observation for lithium phthalocyanine (Barrett, P. A.;Frye, D. A.; Linstead, R. P. J. Chem. Soc. 1938, 1157-1163), and wasisolated by extraction of the reaction residue with dry acetone. Thematerial thereby obtained was used directly without characterization.

The preparation of triple decker 9 (Scheme 11) was performed accordingto a procedure we previously reported (Gross, T.; Chevalier, F.;Lindsey, J. S. Inorg. Chem. 2001, 40, 4762-4774). Thus, CeI₃ inbis(2-methoxyethyl)ether was treated with LiN(SiMe₃)₂ at reflux,affording the putative I-Ce[N(SiMe₃)₂]₂. The addition oftetra-p-tolylporphyrin (8) afforded the corresponding Ce-porphyrinhalf-sandwich complex, which was then treated with Li₂-7 at reflux for10 h. Analytical SEC showed the absence of starting materials and thepresence of the target type-a triple decker 9. The good solubility of 9allowed for purification by standard adsorption chromatography, and 9was isolated in 30% yield. The ¹H NMR analysis of 9 produced a complexsignature due to the effects of the cerium atoms, with most of theresonances being broadened and located at unexpected chemical shifts,but the resonances corresponding to the triallyl moiety were clearlydefined and found in the same portion of the spectrum as for H₂-7. LDMSanalysis of 9 gave a clear signal at the expected mass range. Insummary, the synthesis of triple decker 9 proceeded in a straightforwardmanner. The overall yield from the dicyanophenylenediamine 1 was low(0.6%), but valuable intermediates could be recovered from two of theintervening synthetic steps.

Outlook. The architecture of the axially substituted phthalocyanine isshown in FIG. 8. Attachment of the tether to the central ligand of thetriple deckers, using the new phthalocyanine substitution pattern,affords an axially symmetric triple decker. The resulting triple deckerno longer has a camshaft rotation and should give a small molecularfootprint and, thus, a high charge density upon attachment to anelectroactive surface. A similar architecture would be available in atype-b triple decker via attachment to the central porphyrin, butrational methods for synthesis of type-b triple deckers are not yetavailable. The present strategy provides the first route wherein atriple decker is centrally disposed with respect to a linkingsubstituent, which in this case is the all-carbon tripod for surfaceattachment.

General. ¹H (400 MHz) and ¹³C (75 MHz) NMR spectra were obtained inCDCl₃ unless noted otherwise. Silica gel (40 μm average particle size)was used for column chromatography. Purified acetone was prepared fromreagent grade acetone by distillation over potassium permanganate andthe distillate was stored over anhydrous K₂CO₃ prior to use. Othersolvents used as received commercially include N-methylpyrrolidinone(NMP=1-methyl-2-pyrrolidinone, anhydrous), DMAE (redistilled grade), andMeOH (anhydrous). NaOMe was employed as a 25 wt % solution in MeOH. Allother chemicals were reagent grade and were used as received. Absorptionand emission data were measured in THF. The fluorescence quantum yieldof H₂-7 was measured by comparison to tetra-tert-butylphthalocyanine,which was itself measured in both THF and CHCl₃ set at Φ_(f)=0.70 in THF(by comparison to the reported Φ_(f) of 0.77 fortetra-tert-butylphthalocyanine CHCl₃ with correction for the indices ofrefraction of the different samples) (Teuchner, K.; Pfarrherr, A.;Stiel, H.; Freyer, W.; Leupold, D. Photochem. Photobiol. 1993, 57,465-471).

Example 31

Noncommercial Compounds: Compounds 1 (compound 3 in examples 1-30), 6(Claessens, C. G.; Gonzalez-Rodriguez, D.; del Rey, B.; Torres, T.;Mark, G.; Schuchmann, H. P.; von Sonntag, C.; MacDonald, J. G.; Nohr, R.S. Eur. J. Org. Chem. 2003, 14, 2547-2551), and 8 (Adler, A. D.; Longo,F. R.; Finarelli, J. D.; Goldmacher, J.; Assour, J.; Korsakoff, L. J.Org. Chem. 1967, 32, 476) were prepared according to the literature.

Example 32

4-(4-Allylhepta-1,6-dien-4-yl)aniline. Following a literature procedure(Lin, S.-Y.; Hojjat, M; Strekowski, L. Synth. Commun. 1997, 27,1975-1980) at 80-fold larger scale, a 2 M solution of allyl magnesiumchloride in THF (0.400 L, 0.800 mol) was diluted with additional THF(1.00 L) and then treated dropwise with a solution of4-(trifluoromethyl)aniline (19.9 mL, 0.160 mol) in THF (210 mL) at −50°C. under argon. After complete addition the sides of the reaction flaskwere rinsed with additional THF (150 mL). The resulting solution washeated at reflux. The reaction was monitored by TLC for the completeconsumption of 4-(trifluoromethyl)aniline. After 3.5 h, the mixture wasconcentrated and then CH₂Cl₂ was added. The organic solution was washedwith water, dried (Na₂SO₄), and filtered. The filtrate was concentratedand chromatographed [silica, CH₂Cl₂/hexanes (2:1)], affording a paleyellow solid (31.7 g, 87%): ¹H NMR δ 2.36-2.43 (m, 6H), 3.48-3.66 (br,2H), 4.94-5.06 (m, 6H), 5.50-5.64 (m, 3H), 6.62-6.70 (m, 2H), 7.06-7.12(m, 2H); ¹³C NMR δ 42.1, 42.6, 115.0, 117.5, 127.6, 135.0, 135.8, 144.1;FABMS obsd 228.1757, calcd 228.1752 [(M+H)⁺, M=C₁₆H₂₁N].

1-(4-Allylhepta-1,6-dien-4-yl)-4-iodobenzene. A solution of conc.HCl/H₂O (1:1 v/v, 44 mL) was added to a solution of4-(4-allylhepta-1,6-dien-4-yl)aniline (11.4 g, 50.2 mmol) in THF (80mL). The mixture was stirred at room temperature for 75 min, then cooledto 0-5° C. A chilled solution of NaNO₂ (7.99 g, 116 mmol) in water (80mL) was added while maintaining the temperature of the reaction mixturebelow 5° C. Additional H₂O (30 mL) was added. The reaction mixture wastested for the presence of nitrous acid with starch paper. A solution ofKI (14.2 g, 85.5 mmol) in H₂O (16 mL) cooled to ˜5° C. was added, againmaintaining the mixture at <5° C. throughout the addition. AdditionalH₂O (24 mL) and THF (150 mL) were added. The reaction mixture was thengradually allowed to warm to room temperature. After ˜6.5 h, thereaction mixture was neutralized with saturated aqueous Na₂CO₃ and thenfiltered. The filtrate was concentrated. The resulting residue wasdissolved in CH₂Cl₂ and washed with water. The organic phase was dried(Na₂SO₄), concentrated and chromatographed (silica, hexanes) to afford acolorless liquid (4.73 g, 28%): ¹H NMR (300 MHz) δ 2.38-2.50 (m, 6H),4.94-5.12 (m, 6H), 5.44-5.64 (m, 3H), 7.00-7.12 (m, 2H), 7.58-7.70 (m,2H); ¹³C NMR δ 41.8, 42.0, 43.5, 91.4, 117.8, 118.2, 129.1, 134.2;137.3, 145.8.

4-(4-Allylhepta-1,6-dien-4-yl)benzonitrile. A mixture of1-(4-allylhepta-1,6-dien-4-yl)-4-iodobenzene (5.07 g, 15.0 mmol), CuCN(2.03 g, 22.6 mmol) and DMF (50 mL) was heated over the course of 30 minuntil refluxing with continued reflux for 3 h. The reaction wasmonitored by TLC. The mixture was poured into a flask containing crushedice and concentrated aqueous NH₄OH (200 mL). The resulting mixture wasbubbled with oxygen for 14 h. The resulting dark blue mixture was thenfiltered. The layers of the filtrate were separated and the aqueouslayer was extracted with CH₂Cl₂. The combined organic layer was dried(Na₂SO₄), concentrated and chromatographed [silica, hexanes/ethylacetate (19:1)] to afford a colorless liquid (3.17 g, 89%): IR(CH₂Cl₂)2230 cm⁻¹; ¹H NMR (300 MHz) δ 2.40-2.54 (m, 6H), 4.94-5.12 (m, 6H),5.40-5.62 (m, 3H), 7.36-7.48 (m, 2H), 7.56-7.68 (m, 2H); ¹³C NMR δ 41.6,44.2, 109.8, 118.6, 119.1, 127.8, 132.0, 133.5, 151.7; FABMS obsd238.1589, calcd 238.1596 [(M+H)⁺, M=C₁₇H₁₉N].

4-(4-Allylhepta-1,6-dien-4-yl)benzaldehyde (2). A solution of4-(4-allylhepta-1,6-dien-4-yl)benzonitrile (2.21 g, 9.32 mmol) in CH₂Cl₂(25 mL) was cooled to 0° C. and was treated dropwise with a 1 M solutionof DIBAL-H in hexanes (11.2 mL, 11.2 mmol). The solution was allowed toslowly warm to room temperature. The reaction was monitored by TLC.After 3 h, the reaction mixture was poured into a beaker containingcrushed ice and 6 N HCl. The mixture was stirred for about 1 h. Thelayers were separated and the aqueous phase was extracted with CH₂Cl₂.The combined organic layer was washed with aqueous NaHCO₃ followed bywater. The organic layer was dried (Na₂SO₄), concentrated andchromatographed [silica, hexanes/ethyl acetate (19:1)] to afford acolorless liquid (2.04 g, 91%): IR(CH₂Cl₂) 3078, 1705 cm⁻¹; 1H NMR (300MHz) δ 2.44-2.59 (m, 6H), 4.94-5.14 (m, 6H), 5.44-5.66 (m, 3H),7.45-7.58 (m, 2H), 7.80-7.93 (m, 2H), 9.99 (s, 1H); ¹³C NMR δ 41.8,44.3, 118.4, 127.6, 129.6, 133.8, 134.4, 153.4, 192.0; FABMS obsd241.1597, calcd 241.1592 [(M+H)⁺, M=C₁₇H₂₀O].

Example 33

2-(4-(4-Allylhepta-1,6-dien-4-yl)phenyl)-5,6-dicyanobenzimidazole (3). Asolution of 1 (198 mg, 1.25 mmol) in NMP (2.5 mL) and a solution of 2(300 mg, 1.25 mmol) in NMP (3.5 mL) were combined in a flask fitted witha Hickman still. The mixture was heated at 120° C. and stirred for 2 h.Then FeCl₃.6H₂O (17 mg, 63 μmol) was added and oxygen was bubbledthrough the mixture with continued heating and stirring for 20 h. Thecooled reaction mixture was diluted with ethyl acetate. The organicsolution was washed with water and brine. The organic layer was dried(Na₂SO₄), filtered, concentrated, and chromatographed (silica, CH₂Cl₂w/ethyl acetate gradient of 0-5%). Fractions containing the desiredcompound were concentrated to give a reddish solid, which waschromatographed over a short plug of alumina (CH₂Cl₂ w/ethyl acetategradient of 10-100%) yielding a colorless solid (268 mg, 57%): mp264-266° C.; ¹H NMR (d₆-acetone) δ 2.57 (d, J=7.2 Hz, 6H), 4.88-5.11 (m,6H), 5.56-5.69 (m, 3H), 7.65 (d, J=8.8 Hz, 2H), 8.26 (d, J=8.8 Hz, 2H),12.89 (brs, 1H); ¹³C NMR (d₆-acetone) δ 41.6, 44.0, 108.2, 116.9, 117.7,126.4, 127.3, 128.0, 134.4, 150.2; FABMS obsd 379.1909, calcd 379.1923(C₂₅H₂₂N₄).

Note: Chromatography of the reaction mixture is aided by the strong bluefluorescence of the product that is visible when: illuminating thecolumn with a hand-held long wave UV lamp.

Example 34

2-(4-(4-Allylhepta-1,6-dien-4-yl)phenyl)-5,6-dicyano-1-propylbenzimidazole(4). Following a reported procedure, a sample of 3 (265 mg, 0.70 mmol)in NMP (2.5 mL) was heated to 120° C. and treated with DBU (105 μL, 0.70mmol). After stirring for 2 min, iodopropane (105 μL, 0.70 mmol) wasadded and the mixture was stirred for 15 min. A second dose of DBU (68μL, 0.70 mmol), followed by iodopropane (68 μL, 0.70 mmol), was added,and 15 min later, a third identical round of DBU and iodopropane wasagain added. After the mixture was stirred for 15 min, the reactionmixture was allowed to cool and was diluted with ethyl acetate. Theorganic solution was washed with water and brine. The organic layer wasdried (Na₂SO₄), filtered, concentrated, and chromatographed (silica,CH₂Cl₂ w/ethyl acetate gradient of 0-5%). Some starting material wasrecovered (83 mg, 31%), and fractions containing the product wereconcentrated to give a colorless solid (183 mg, 62%): mp 132-134° C.; ¹HNMR δ 0.92 (t, J=8.0 Hz, 3H), 1.82-1.93 (m, 2H), 2.52 (d, J=8.8 Hz, 6H),4.31 (t, J=7.6 Hz, 2H), 4.98-5.09 (m, 6H), 5.50-5.63 (3H), 7.53 (d,J=8.4 Hz, 2H), 7.70 (d, J=8.4 Hz, 2H), 7.88 (s, 1H), 8.19 (s, 1H); ¹³CNMR δ 11.4, 23.5, 41.9, 44.1, 47.3, 108.5, 109.0, 116.7, 116.8, 118.5,126.1, 126.4, 127.9, 129.2, 134.0, 137.9, 145.4, 149.9, 159.4; Anal.Calcd for C₂₈H₂₈N₄: C, 79.97; H, 6.71; N, 13.32; Found: C, 79.93; H,6.73; N, 13.35.

Example 35

2-(4-(4-Allylhepta-1,6-dien-4-yl)phenyl)-1-propylimidazo[4,5-f]isoindole-5,7(1H,6H)-diimine(5). A sample of 4 (105 mg, 0.25 mmol) in anhydrous MeOH (4 mL) under anargon atmosphere was heated at 70° C. When the mixture becamehomogeneous, NaOMe (6 μL of a 25 wt % solution in MeOH, 25 mol) wasadded, the argon line was removed from the apparatus, and ammonia gaswas bubbled through the mixture while the mixture refluxed for 3.5 h.During this time, additional MeOH (0.5 mL) was added at each half hourinterval to prevent the reaction mixture from evaporating to dryness.The reaction flask was allowed to cool to room temperature under anatmosphere of ammonia, and then ammonia flow was stopped. The mixturewas allowed to stand overnight under a slowly flowing stream of argon,whereupon most of the solvent evaporated and a white powder formed inthe vessel. The mixture was taken up by pipette and filtered. Thefiltered material was washed with anhydrous MeOH and dried in vacuo (53mg, 48%): mp 230-232° C. (upon which the sample melted and turned deepgreen). Due to the presence of tautomeric forms of the product, the NHsignals do not all integrate to integers: ¹H NMR (d₈-THF) δ 0.88 (t,J=7.2 Hz, 3H), 1.82-1.96 (m, 2H), 2.56 (d, J=7.2 Hz, 6H), 4.38 (t, J=7.6Hz, 2H), 4.97-5.10 (m, 6H), 5.57-5.70 (m, 3), 7.57 (d, J=8.0 Hz, 2H),7.80 (d, J=8.0 Hz, 2H), 7.84-8.40 (m, 4H); ¹³C NMR (d₈-THF) δ 10.6,23.2, 41.8, 43.7, 46.4, 117.3, 127.2, 129.1, 134.5, 147.8; IR (film):3397, 3276, 3200, 2958, 2927, 1536, 1432, 1149, 1121, 1077, 915.2; Anal.Calcd for C₂₈H₃₁N₅: C, 76.85; H, 7.14; N, 16.00; Found: C, 76.63; H,7.21; N, 16.09.

Note: The title compound does not entirely precipitate from the cooledreaction mixture. The recovery is aided by gently concentrating themixture under a stream of argon until only a small quantity of liquidremains. Once precipitated, 5 does not readily redissolve in drymethanol, but a more soluble yellow byproduct is observed thatredissolved even in preparations wherein the reaction mixture had beenevaporated fully to dryness. Analysis of this byproduct (obtained fromthe methanolic filtrate after separating the product) by ¹H NMRconfirmed that it was not 5, but its identity was not determined.

Example 36

Tribenzo[g,l,q]-(2-{4-(4-Allylhepta-1,6-dien-4-yl)phenyl}-1-propylbenzimidazo[5,6-b])porphyrazine(H₂-7). A 20 mL reaction vial was charged with 5 (43 mg, 98 μmol), 6(169 mg, 392 μmol, 4 equiv), DMAE (5 mL), and a magnetic stirring bar.The vial was capped and heated in an oil bath maintained at 100° C.Periodically, a few microliters of the reaction mixture were removed,diluted into THF, and analyzed by UV-Vis spectroscopy. After 8 h, 6 wasnot observed in the UV-Vis spectrum. The reaction was then cooled toroom temperature and diluted with MeOH (15 mL) and allowed to standovernight. The mixture was centrifuged and the supernatant was removed.MeOH (20 mL) was added to the pellet and the mixture was sonicated andcentrifuged again. After a third MeOH treatment and centrifugation, thepellet was dried in vacuo. The solid residue was suspended in THF (250mL), sonicated, and filtered through celite. The filtrate was set aside.The celite was then added to a Soxhlet thimble and extracted with CH₂Cl₂overnight. The CH₂Cl₂ and THF filtrates were combined and concentratedto dryness. The solid residue was redissolved in a minimum of THF andchromatographed over a column of Bio-Beads SX-3 in THF. The desiredcompound was recovered from the column as a dark blue-green band thatwas closely followed by a blue band (unsubstituted phthalocyanine) and afaint pink band (remaining 6). The fractions containing the desiredcompound were concentrated and rechromatographed over Bio-Beads SX-3 inTHF a second time to remove all pigment impurities. The sample was thenchromatographed (silica, CH₂Cl₂, 1% isopropanol, 5% THF, 5% ethylacetate). Fractions containing the desired compound were concentrated togive a blue solid (25 mg, 32%): IR (KBr pellet): 2918, 1638, 1610, 1518,1426, 1330, 1115, 1001, 912, 740; ¹H NMR (d₈-THF) δ −3.56 (brs, 2H),1.16 (t, J=8.0 Hz, 3H), 2.12-2.24 (m, 2H), 2.75 (d, J=Hz, 6H), 4.53 (t,J=8.0 Hz, 2H), 5.15-5.28 (m, 6H), 5.78-5.91 (m, 3H), 7.61 (t, J=7.2 Hz,1H), 7.71 (t, J=Hz, 1H), 7.76-7.89 (m, 4H), 7.80 (d, J=8.4 Hz, 2H), 8.09(s, 1H), 8.13 (d, J=8.4 Hz, 2H), 8.20 (d, J=6.8 Hz, 1H), 8.47-9.53 (m,2H), 8.57 (s, 1H), 8.63-8.72 (m, 3H); LD-MS obsd, 807.0; FABMS obsd807.3717, calcd 807.3672 [(M+H)⁺; M=C₅₂H₄₂N₁₀]; λ_(abs) (nm) 336, 651,669, 695; λ_(em) (nm) 700, 714; Φ_(f)=0.56.

Example 37

(Li₂-7). A sample of Li ribbon (19 mg, 2.9 mmol) was added to pentanol(14.5 mL) and the mixture was refluxed until the Li was fully consumed(overnight). The mixture was cooled to room temperature and filteredthrough a pipette that was plugged with glass fiber filter paper. Thefiltrate was not titrated but was assumed to be ˜0.2 M. Next a sample ofH₂-7 (25 mg, 31 μmol) was added to pentanol (9.0 mL) and brieflyrefluxed to dissolve all solid. Then the sample was cooled to roomtemperature and the lithium pentoxide solution (1.0 mL) was added. Thevessel was capped with a septum and placed in an oil bath at 140° C. Asthe mixture was refluxed, samples (˜2 μL) were taken periodically,diluted into freshly dried THF (3 mL) and analyzed by UV-Visspectroscopy to monitor the progress of the reaction. After 15 min fromthe start of refluxing, the UV-Vis spectrum of the removed sample hadaltered from the spectrum of the starting pigment (vide supra) to a newspecies having a more narrow Q band. The mixture was kept refluxing fora total of 90 min, although no further change was observed in the UV-Visabsorbance of the removed samples. The reaction mixture was cooled toroom temperature and concentrated to dryness on a high-vacuum rotaryevaporator. The residue was taken up in dry acetone and added to athimble in a Soxhlet apparatus. The residue was extracted with dryacetone until no further color appeared from the thimble. The filtratefrom the extraction was concentrated to dryness. The residue wasdissolved in a minimum of dry acetone and decanted to a vial, takingcare not to transfer any insoluble H₂-7 that may have formed during theextraction. The dark blue solution was then concentrated to dryness togive the product Li₂-7 as a blue solid (10 mg, 39%). Due to thesensitivity of the product to moisture, Li₂-7 was directly used insubsequent synthesis without characterization. The solids left behind inthe evaporation flask and the Soxhlet thimble were combined to recoverthe starting material H₂-7 (15 mg, 60%): λ_(abs) 602, 663, 671.

Example 38

(TTP)Ce(7)Ce(TTP) (9). A 250 mL Schlenk flask was charged with amagnetic stirring bar and introduced into an argon glove box. Ceriumiodide (51 mg, 98 μmol) was added and the flask was sealed with a septumand removed from the glove box. The flask was connected to an argonsource, and the septum was vented with a needle to allow the outflow ofargon gas. The flask was then placed in an ice bath andbis(2-methoxy)ethyl ether (3.0 mL, freshly sparged with argon) wasadded. Then LiN(SiMe₃)₂ (312 μL of a 0.608 M solution freshly preparedin dry THF and sparged with argon) was added, and the mixture wasstirred for 20 min, after which the flask was removed from the ice bathand stirring was continued while the mixture warmed to room temperatureover 40 min. The mixture was then refluxed for 1 h by placing the flaskin an oil bath at 170° C. The flask was then removed from the oil bathlong enough for refluxing to subside, briefly opened to allow theaddition of 8 (H₂TTP) (16 mg, 24 mmol), and closed again and returned tothe bath to reflux for 3 h. Then the vessel was again allowed to cooland opened to remove a small sample for UV-Vis analysis. The sample wasconfirmed as the cerium-porphyrin half-sandwich, so Li₂-7 (10 mg, 12μmol) was added as a slurry in bis(2-methoxyethyl)ether (1.0 mL) and theresulting mixture was refluxed for 10 h under argon. Then the mixturewas allowed to cool to room temperature and concentrated on a highvacuum rotary evaporator. The residue was triturated with MeOH,centrifuged, and the supernatant was discarded. The residue waschromatographed (silica, neat CH₂Cl₂, then CH₂Cl₂ w/1% iPrOH, 5% THF, 5%ethyl acetate). The first band was collected and rechromatographed[silica, hexanes/CH₂Cl₂, (1:2)], and fractions containing the productwere concentrated to give a green-black solid (9.0 mg, 30%): IR (KBrpellet): 2918, 1638, 1610, 1518, 1451, 1404, 1328, 1182, 1070, 986, 797,740, 722; ¹H NMR δ (−2.45)-(−1.30) (m, 20H), 0.75-0.85 (m, 3H), 1.13 (s,24H), 1.73 (d, J=7.2 Hz, 6H), 1.90-2.20 (m, 6H), 2.80-3.60 (m, 20H),2.75 (d, J=Hz, 6H), 4.35-4.42 (m, 6H), 4.68-4.82 (m, 3H), 5.45-5.62 (m,2H), 6.20-6.35 (m, 2H), 7.09 (s, 8H), 10.34 (s, 8H); LD-MS obsd, 2419.3;calcd 2420.74 (C₁₄₈H₁₁₂Ce₂N₁₈); λ_(abs) (nm) 359, 419, 493, 549, 608.

The foregoing is illustrative of the present invention, and is not to beconstrued as limiting thereof. The invention is defined by the followingclaims, with equivalents of the claims to be included therein.

1-24. (canceled)
 25. A benzazoloporphyrazine compound having at leastone independently selected substituent R at a 2 position of an azologroup thereof, wherein R is a surface attachment group or cross couplinggroup, and subject to the proviso that R is not H or (CH₂)_(n)CH₃ wheren is 0-7.
 26. A benzazoloporphyrazine according to claim 25, whereinsaid benzazoloporphyrazine is selected from the group consisting ofbenzimidazoporphyrazines, benzoxazoporphyrazines,benzthiazoporphyrazines, and benzselenazoporphyrazines.
 27. A compoundof claim 25, wherein said compound is atrans-bis(2-R-benzazolo)porphyrazine having a pair of substituents R ateach 2 position of each of the pair of oppositely facing azolo groupsthereof.
 28. A benzazoloporphyrazine according to claim 27, wherein saidbenzazoloporphyrazine is selected from the group consisting ofbenzimidazoporphyrazines, benzoxazoporphyrazines,benzthiazoporphyrazines, and benzselenazoporphyrazines.
 29. The compoundof claim 25, wherein said compound is a 2-R-benzazoloporphyrazinecompound having a single substituent R at the 2 position of the azologroup thereof.
 30. A benzazoloporphyrazine according to claim 29,wherein said benzazoloporphyrazine is selected from the group consistingof benzimidazoporphyrazines, benzoxazoporphyrazines,benzthiazoporphyrazines, and benzselenazoporphyrazines.
 31. The compoundof claim 25, wherein said compound is atetrakis(2-R-benzazolo)porphyrazine compound having a substituent R ateach 2 position of each of the four azolo groups thereof.
 32. Abenzazoloporphyrazine according to claim 31, wherein saidbenzazoloporphyrazine is selected from the group consisting ofbenzimidazoporphyrazines, benzoxazoporphyrazines,benzthiazoporphyrazines, and benzselenazoporphyrazines.
 33. Abenzazoloporphyrazine according to claim 25, wherein saidbenzazoloporphyrazine is selected from the group consisting of:2-R-5,6-benzimidazoporphyrazines;trans-bis(2-R-5,6-benzimidazo)porphyrazines;tribenzo(2-R-5,6-benzimidazo)porphyrazines;trans-dibenzo-bis(2-R-5,6-benzimidazo)porphyrazines;tetrakis(2-R-5,6-benzimidazo)porphyrazines;2-R-5,6-benzoxazoporphyrazines;trans-bis(2-R-5,6-benzoxazo)porphyrazines;tribenzo(2-R-5,6-benzoxazo)porphyrazines;trans-dibenzo-bis(2-R-5,6-benzoxazo)porphyrazines;tetrakis(2-R-5,6-benzoxazo)porphyrazines;2-R-5,6-benzthiazoporphyrazines;trans-bis(2-R-5,6-benzthiazo)porphyrazines;tribenzo(2-R-5,6-benzthiazo)porphyrazines;trans-dibenzo-bis(2-R-5,6-benzthiazo)porphyrazines;tetrakis(2-R-5,6-benzthiazo)porphyrazines;2-R-5,6-benzselenazoporphyrazines;trans-bis(2-R-5,6-benzselenazo)porphyrazines;tribenzo(2-R-5,6-benzselenazo)porphyrazines;trans-dibenzo-bis(2-R-5,6-benzselenazo)porphyrazines; andtetrakis(2-R-5,6-benzselenazo)porphyrazines.
 34. The compound of claim25, wherein R comprises a cross-coupling group selected from the groupconsisting of halo, alkenyl, alkynyl, and amine cross-coupling groups,each of which is directly coupled to said compound or coupled to saidcompound by a linker group.
 35. The compound of claim 25, wherein Rcomprises a surface attachment group selected from the group consistingof: iodo, bromo, chloro, cyano, amino, alkenyl, alkynyl, hydroxy,mercapto, selenyl, telluro, S-acetylthio, Se-acetylseleno, andTe-acetyltelluro, each of which is directly coupled to said compound orcoupled to said compound by a linker group. 36-37. (canceled)
 38. Apolymer comprising from 2 to 50 benzazoloporphyrazines of claim 25covalently coupled to one another.
 39. (canceled)
 40. A sandwichcoordination compound, wherein at least one member thereof is abenzazoloporphyrazine of claim
 25. 41-42. (canceled)
 43. A polymer offrom 2 to 50 linked sandwich coordination compounds, wherein each ofsaid sandwich coordination compounds comprises a benzazoloporphyrazineof claim 25 linked to a benzazoloporphyrazine of an adjacent sandwichcoordination compound.
 44. (canceled)
 45. A method of making atrans-bis(2-R-benzazolo)porphyrazine having a pair of substituents R ateach 2 position of a pair of oppositely facing azolo groups thereof,wherein each R is a surface attachment group or cross-coupling group,said method comprising: reacting a compound of Formula III:

wherein: X is selected from the group consisting of N, O, S, and Se; Ris a surface attachment group or cross-coupling group; and R¹ is absentor when X is N is H, C1-C40 linear or branched, substituted orunsubstituted alkyl; and each R² is independently selected from thegroup consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, aryl(including phenyl), halo, hydroxy, alkoxy, alkylthio, pyridyl, cyano,thiocyanato, nitro, amino, alkylamino, acyl, sulfoxyl, sulfonyl, amido,and carbamoyl; or an R² group is linked to an R² group on an additionalcompound of formula III by a linker group; with a trihaloisoindolenineto produce said trans-bis(2-R-benzazolo)porphyrazine compound.
 46. Themethod of claim 45, wherein said reacting step is carried out in thepresence of an acid acceptor and a hydroquinone compound which candonate hydrogen atoms.
 47. The method of claim 45, wherein saidtrihaloisoindolenine is a compound of Formula IV:

wherein X², X³, and X⁴ are each halo and each R² is as given above, or apair of adjacent R² groups form an annulated ring or annulated ringsystem.
 48. The method of claim 47, wherein: saidtrans-bis(2-R-benzazolo)porphyrazine is a compound of Formula IIa orIIb:

wherein M is a metal or a pair of hydrogens; and each of X, R, R¹, andR² are as given above.
 49. A method of making a2-R-benzazoloporphyrazine compound having at least one independentlyselected substituent R at a 2 position of an azolo group thereof,wherein R is a surface attachment group or cross-coupling group, saidmethod comprising: reacting a compound of Formula III:

wherein: X is selected from the group consisting of N, O, S, and Se; Ris a surface attachment group or cross-coupling group; R¹ is absent orwhen X is N is H, C1-C40 linear or branched, substituted orunsubstituted alkyl, and each R² is independently selected from thegroup consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, halo,hydroxy, alkoxy, alkylthio, pyridyl, cyano, thiocyanato, nitro, amino,alkylamino, acyl, sulfoxyl, sulfonyl, amido, and carbamoyl; or an R²group is linked to an R² group on an additional compound of formula IIIby a linker group; with a substituted or unsubstitutedboron-subpporphyrazine in an organic solvent at an elevated temperatureto produce said 2-R benzazoloporphyrazine compound.
 50. The method ofclaim 49, wherein said 2-benzazoloporphyrazine is a compound of FormulaV:

wherein M is a metal or pair of hydrogens, and each of X, R, R¹ and R²is as given above.
 51. A method of making a 2-R-benzazoloporphyrazinecompound, wherein R is a surface attachment group or cross-couplinggroup, said method comprising: reacting a compound of Formula VI:

wherein: X is selected from the group consisting of N, O, S, and Se; Ris a surface attachment group or cross-coupling group; R¹ is absent orwhen X is N is H, C1-C40 linear or branched, substituted orunsubstituted alkyl, and each R² is independently selected from thegroup consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, halo,hydroxy, alkoxy, alkylthio, pyridyl, cyano, thiocyanato, nitro, amino,alkylamino, acyl, sulfoxyl, sulfonyl, amido, and carbamoyl; or an R²group is linked to an R² group on an additional compound of formula VIby a linker group; with a compound of Formula VII:

where R² is as given above, or an adjacent pair of R² groups on the samering form a fused or annulated ring or ring system; in an alcohol in thepresence of an alkyl amine or metal base, and optionally in the presenceof a metal halide, to produce said 2-R-benzazoloporphyrazine compound.52. The method of claim 51, wherein said 2-R benzazoloporphyrazine is acompound of Formula V:

wherein M is a metal or a pair of hydrogens; and each of X, R, R¹ and R²is as given above.
 53. A method of making a tetrakis(2-R-benzazolo)porphyrazine compound having four substituents R at the 2position of each azolo group thereof, wherein R is a surface attachmentgroup or cross-coupling group, said method comprising: tetramerizing acompound of Formula III:

wherein: X is selected from the group consisting of N, O, S, and Se; Ris a surface attachment group or cross-coupling group; R¹ is absent orwhen X is N is H, C₁-C₄₀ linear or branched, substituted orunsubstituted alkyl, and each R² is independently selected from thegroup consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, halo,hydroxy, alkoxy, alkylthio, pyridyl, cyano, thiocyanato, nitro, amino,alkylamino, acyl, sulfoxyl, sulfonyl, amido, and carbamoyl; or an R²group is linked to an R² group on an additional compound of formula IIIby a linker group; in a polar protic solvent at an elevated temperatureto produce said tetrakis(2-R-benzazolo)porphyrazine compound.
 54. Themethod of claim 53, wherein said tetrakis(2-R-benzazolo)porphyrazine isa compound of Formula VIIIa-d:

wherein M is a metal or a pair of hydrogens and each of X, R, R¹ and R²is as given above.
 55. A method of making a tetrakis(2-Rbenzazolo)porphyrazine compound having four substituents R at the 2position of each azolo group thereof, wherein R is a surface attachmentgroup or cross-coupling group, said method comprising: reacting acompound of Formula VI:

wherein: X is selected from the group consisting of N, O, S, and Se; Ris a surface attachment group or cross-coupling group; R¹ is absent orwhen X is N is H, C1-C40 linear or branched, substituted orunsubstituted alkyl, and each R² is independently selected from thegroup consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, halo,hydroxy, alkoxy, alkylthio, pyridyl, cyano, thiocyanato, nitro, amino,alkylamino, acyl, sulfoxyl, sulfonyl, amido, and carbamoyl; or an R²group is linked to an R² group on an additional compound of formula VIby a linker group; in an alcohol in the presence of an alkyl amine ormetal base, and optionally in the presence of a metal halide, to producesaid compound.
 56. The method of claim 55, wherein said tetrakis(2-Rbenzazolo)porphyrazine is a compound of Formula VIIIa-d:

wherein M is a metal or a pair of hydrogens and each of X, R, R¹ and R²is as given above.
 57. A method of making a compound of Formula III:

wherein: X is selected from the group consisting of N, O, S, and Se; Ris a surface attachment group or cross-coupling group; R¹ is absent orwhen X is N is H, C1-C40 linear or branched, substituted orunsubstituted alkyl, and each R² is independently selected from thegroup consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, halo,hydroxy, alkoxy, alkylthio, pyridyl, cyano, thiocyanato, nitro, amino,alkylamino, acyl, sulfoxyl, sulfonyl, amido, and carbamoyl; said methodcomprising reacting a compound of Formula VI

wherein each of X, R, R¹ and R² is as given above in either (a) a polarprotic solvent with an alkoxide base and ammonia gas at an elevatedtemperature, or (b) a polar aprotic solvent containing NaNH₂, to producesaid compound of Formula III.
 58. A method of making a compound ofFormula VI:

wherein: X is N, O, S or Se; R is a surface attachment group orcross-coupling group; R¹ is H, C1-C40 linear or branched, substituted orunsubstituted alkyl, and each R² is independently selected from thegroup consisting of H, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, halo,hydroxy, alkoxy, alkylthio, pyridyl, cyano, thiocyanato, nitro, amino,alkylamino, acyl, sulfoxyl, sulfonyl, amido, and carbamoyl; said methodcomprising reacting a compound of Formula IX:

where X′ is NH₂, SH, OH, or SeH with an aldehyde of the formula RCHO,wherein R is as given above in a polar aprotic solvent in the presenceof an oxidant to produce a reaction product; and then optionallyreacting said reaction product with a compound of the formula R¹X¹,where X¹ is halo, tosyl, or triflate, to produce said compound ofFormula VI.
 59. A method of making a compound of the Formula IX:

wherein each R² is independently selected from the group consisting ofH, alkyl, alkenyl, alkynyl, cycloalkyl, aryl, halo, hydroxy, alkoxy,alkylthio, pyridyl, cyano, thiocyanato, nitro, amino, alkylamino, acyl,sulfoxyl, sulfonyl, amido, and carbamoyl; said method comprisingreacting a compound of Formula X

in a polar aprotic solvent with a cyanation reagent to produce saidcompound of Formula IX.